My personal experience in the sicilian four knights has been really positive. It's my favorite line because I always get a playable and active position out of the opening.
The reason is that at my level most of the players don't play the critical line 6. Ndb5 (with the idea 6. ...d6 7. Bf4 e5 8. Bg5 transposing into the complicated sveshnikov) which isn't surprising since only people who know theory would play Ndb5. I'll discuss it later.
So most of the players play a developing move like Bc4 or Be3. The reason why I like this opening is that because black didn't play d6 he is able to develop his bishop actively to b4 pressuring the center.
Sometimes Qa5 can be played but most important is the fact that black can push d5 in most of the lines. In no other sicilian it is so easy to push d5. Black gets active play and good winning chances.
The reason why I think that the sicilian four knights is a good opening is that only really strong players who know the theory will move their knight a second time with Ndb5 thus playing the critical main line. Here I would suggest Bb4 instead of d6 because the sveshnikov is really complicated and to be honest I don't understand a lot of the positions which arise out of the sveshnikov.
After 6. ... Bb4 7. a3 Bc3:+ 8. Nc3: d5 9. ed ed you get a IQP-position which is maybe a little easier to handle if you already play IQP-positions. I had this variation only once against an IM in a local rapid tournament and he destroyed me (Never in my life I lost so brutally.
). But I don't think it was because of the opening.
). But I don't think it was because of the opening.Another critical line I saw in a book was 6. Nc6: bc 7. Ne4. To be honest I don't know much about this line and I didn't studied it in depth nor did I encounter it online or OTB.
My first impression is that the position are slightly uncomfortable with black.
Maybe you have some advice?
Long story short: I think the sicilian four knights is a good practical weapon which offers active piece play and the possibility to play the thematic sicilian pawn break d5 most of the time.
It doesn't take much time to prepare it, it's not so theory heavy. After a few games you can familiarize yourself really quickly with the typical plans and ideas.
The only problem I see is in the main lines. But I don't encounter them in most of my games but it can't hurt to have something in store for these critical lines. As mentioned above I recommend Bb4 against Ndb5 because the sveshnikov is too much theory.
Against Nc6: ... well maybe you have some ideas.
Have fun!
