That percentage seems good and at the very least standard for a Black opening. Look what 365chess shows of some other openings after 1.e4. After 1...e5 White 41.5% Black 29.2% for example.
Super GM Segei Tiviakov has the Scandinavian as one of his main openings.
As a 1.e4 player I don't like to face the Scandinavian because I don't see it often and don't know much about it, meanwhile the people who use it become experts in it.
Dolphin27 said what I was going to say: the percentages you quoted are typical for *all* sound openings: White always has an edge of about 5-10% when the game starts. Notice that when you get around 7-10 moves into any sound opening, the draw percentage rises to about 30%, sometimes even up to 70%, and of the remaining percentage the difference of which side wins becomes much more even. Therefore if you're really interested in how an opening fares, statistically, check specific variations deeper than just the first move.
As White the Scandinavian makes me a little nervous, too, just as Dolphin27 said. The outstanding benefit of the Scandinavian that I see is that Black is said to equalize in an e-pawn opening as soon as he can safely play ...d5, which in this case is supposedly on his first move! Therefore if Black can survive that somewhat premature attempt at equalization, logic says he'll have a good game from the start. The old fashioned 2. exd5 Qxd5 3. Nc3 does cause Black to lose a tempo, which is bad for Black, but the more modern 2. exd5 Nf6 3. Nc3 Nxd5 looks to me like it's difficult or even impossible to refute convincingly, which adds to my nervousness about that defense, especially in the hands of an expert.
The Scandinavian is Unsound and very close to Refuted.
White has a narrow path in beating black in this continuation no matter what black does. Super GM's have proved this and so have very strong chess engines.
Usually high levels only play this line with the hopes there opponent has forgotten the theory or if they feel they can out prepare there opponent(with home preparation) etc.
In a beginner level, interimdate level, advance level, and even Title level you can get away with playing this line. Usually players don't know how to play against it. When you start to get into the Title GM level thats when you face hard problems. They really don't play it that much.
If you look at this line with an engine you will see the engine will win with white every time from this position. The only real question would be if you as a human will be able to follow the narrow path to victory lol. Most humans forget stuff lol. So that will be the real test against this line. Remembering your theory and correct moves lol.
Its sound as long as you dont go for stuff like portuguese gambit or icelandic gambit.
I play the Icelandic gambit and it has always worked fine for me.
but the more modern 2. exd5 Nf6 3. Nc3 Nxd5 looks to me like it's difficult or even impossible to refute convincingly, which adds to my nervousness about that defense, especially in the hands of an expert.
except white has many better options than 3.Nc3; 3.Nf3, 3.d4 and even 3.Bb5+ all work better than the passive 3.Nc3; the first 2 options Nf3 and d4 will lead to very similar positions often with a slight change in move order.
edit: thx unusualmove, i forgot the c4 lines completely.
After 1.e4 d5 2.ed Nf6, 3.c4 c6 4.Nc3! (4.dc Nxc6 is too greedy) cd 5.Nf3 seems to me as a good way to play, but it only makes sense if you have the Panov-Botvinnik Attack (reached by the move order 1.e4 c6 2.d4 d5 3.ed cd 4.c4) in your arsenal.
but the more modern 2. exd5 Nf6 3. Nc3 Nxd5 looks to me like it's difficult or even impossible to refute convincingly, which adds to my nervousness about that defense, especially in the hands of an expert.
except white has many better options than 3.Nc3; 3.Nf3, 3.d4 and even 3.Bb5+ all work better than the passive 3.Nc3; the first 2 options Nf3 and d4 will lead to very similar positions often with a slight change in move order.
"the passive Nc3" ??
but the more modern 2. exd5 Nf6 3. Nc3 Nxd5 looks to me like it's difficult or even impossible to refute convincingly, which adds to my nervousness about that defense, especially in the hands of an expert.
except white has many better options than 3.Nc3; 3.Nf3, 3.d4 and even 3.Bb5+ all work better than the passive 3.Nc3; the first 2 options Nf3 and d4 will lead to very similar positions often with a slight change in move order.
"the passive Nc3" ??
I consider both d4 and Nf3 to give white more play. calling Nc3 it passive is obviously a bit lol, but english is not my native language so please forgive my lack of a better term.
but the more modern 2. exd5 Nf6 3. Nc3 Nxd5 looks to me like it's difficult or even impossible to refute convincingly, which adds to my nervousness about that defense, especially in the hands of an expert.
except white has many better options than 3.Nc3; 3.Nf3, 3.d4 and even 3.Bb5+ all work better than the passive 3.Nc3; the first 2 options Nf3 and d4 will lead to very similar positions often with a slight change in move order.
"the passive Nc3" ??
I consider both d4 and Nf3 to give white more play. calling Nc3 it passive is obviously a bit lol, but english is not my native language so please forgive my lack of a better term.
I understand, sorry for my rash response. BTW the point of Nc3 is to drive away the Black Queen so that the liquidating ...e5 loses yet another tempo. Following this logic 3.d4 could be satisfyingly met by 3...e5! 3.Nf3 is a bit more logical as it prepares d4 followed by c4 (which Nc3 hinders) and it prevents e5, there is probably a reason why it is not the mainline, though.
Good tips, X_PLAYER_J_X and KarryGasparOv. I think you two just modified the line I've been playing for a very long time.
There are two distinct main lines after 1. e4 d5
They are:
I believe the line 1. e4 d5 2. exd5 Nf6 leads to a White advantage.
Also believe the line 1. e4 d5 2. Nc3 is equal
Also believe the line 1. e4 d5 2. exd5 Qxd5 3. Nf3 Bg4 is equal
Also believe the line 1. e4 d5 2. exd5 Qxd5 3. Nc3 Qd6 gives White the advantage.
Also believe that the line 1. e4 d5 2. exd5 Qxd5 3. Nc3 Qa5 is very good for White if he knows what he is doing.
I have won many games vs players from expert to GM with the black side of this last line. Also wrote a book on the black side of this last line.
Sorry, but methinks the Scandinavian is a poor line if White knows what he is doing. 
On Chessgames.com there's a collection of 78 games Tiviakov has played using the Scandinavian against high level opposition, winning in 22, drawing in 42, and only losing in 14.
The 3.Nf3 line against the Scandinavian is what IM Andrew Greet covers in his book Beating Unusual Chess Defenses. Also GM (then an IM) Bryan Smith made a DVD about it for Chesslecture.
The annoying thing about the Scandinavian is that the person is always going to get their opening on the board because there aren't many Anti-Scandinavians at all. They will likely be more experienced in the opening even against 3.Nf3. Though perhaps we can hope that if the typical Scandinavian knows the opening well, and the typical e4 player doesn't, then the Scandinavian player will get used to playing people who don't know nearly as much as them. Then if you just learn more about it than the average e4 player it may be enough.
I have the book Beating Unusual Chess Defenses. It is generally a good book but it has some incorrect analysis on the line 1. e4 d5 2. exd5 Qxd5
3. Nf3 Bg4
Its sound as long as you dont go for stuff like portuguese gambit or icelandic gambit.
This line very probably equalizes for Black. [however there are lines where White can get the advantage vs the Scandinavian]
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While surfing the web on the Scandinavian Open, I found on 365chess.com that in (on the website) recorded games black has won 31 percent of games after exd5. White has a recorded 41 percent. Considering that this opening has always been my go to response to 1. e4 ever since I watched a local IM use this defense against 3 other IMs on my own board when I was young, it was a little upsetting to find out that this opening might not be sound for Black. The posting of comments, high-rated games, variation, etc is appreciated.