Certainly you studied that stuff way deeper than I did but from a practical point of view I'd say the exchange sac line is sound enough to give it a try at least once in a while.
I guess it's unclear whether it's 100% sound or not but it's also recommended by Magnus' second Peter Heine Nielsen in his video series, which is a good sign even tough the engine gives White +1 in some of the lines. I'd say from a human point of view they are rather unclear and your safer king and superior prep kinda compensates for the exchange.
About Negi's 15. h4 I wouldn't be too concerned. Wesley So in 2019 played 15. b3 in a must win KO game, which indicates that h4 isn't the most critical try for White.
After 15... b4 Negi recommends going for an endgame where your rooks are active on the 2rd rank. The engine doesn't give White much advantage so with some analysis it shouldn't be impossible to work that out a bit closer to a draw
However, Gawain Jones recommends 15... h5. Cant say much about it as I just skimmed over that chapter very quickly. He seems to like it and I think it also has additional surprise value as it hasn't been played much in high level games. So you will very likely be better prepared unless your opponent is a Dragon player himself and has the Jones books.
Playing 11... Nxd4 is a safer choice but you kinda "throw away" tons of your prep as it also rules out a lot of other fun lines where White goes for 12. h4 instead of 12. Kb1. You would hardly ever get these positions anymore but you still would have to be ready for that stuff as White can move-order you into those lines by throwing in 10. h4 h5 first instead of 10. 0-0-0
OTB it makes sense anyway to switch between the lines in order to not be too predictable. So I'd probably keep the exchange sac in my repertoire and just see how it goes.
Hey, so I'm a USCF Expert (2075) (approaching the Master level) and have the Dragon as my main defence against e4. I know a LOT of Dragon theory and have Gawain Jones' 2 high quality volumes on the Dragon. I have no problems against any of the minor systems like the 6.Be2 Classical, Fianchetto, Levenfish, etc. Against 9.O-O-O I think I am generally fine with 9...d5 and can make the draw (You have to suffer a bit to make the draw in the 12.Bd4...Bxd4 lines but Black can make a draw and in other lines I think Black can fairly comfortably draw, with plenty of winning chances along the way). The issue for me (to some extent) comes in the 9.Bc4 lines.
Here is the position where I feel the big choice. I generally play the 11...Ne5 lines because I like them. First of all, there are ZERO theoretical problems (other than memorization
) after 12. h4...h5, and I feel like Black often gets an edge. The problem is definitely 12. Kb1, which is without question the best move. I play Nc4 (I think Black is just worse after 12...a6 and 12...Re8, even though the latter requires quite a bit of accuracy to establish an edge), as Jones "recommends" (He actually recommends 11...Nxd4, which is less complex but is definitely not refutable(Black trades the winning chances of chaos to ensure they won't be blown off the board)) in his extra chapter where he basically gives recommendations for Black in the 11...Ne5 12. Kb1 lines, but acknowledges that he "can't promise that every variation that follows will be completely sound". All the important lines follow
Here is the key position. White has a pair of relevant follow-ups. The first is 15.b3, after which the insane 15...b4! 16. bxc4...bxc3 17. Qxc3...Qc7 are practically forced. So far, White has not proven a clear refutation to my knowledge, but Black is definitely on the edge of the cliff. This line generally works well for Black in practice (particularly in blitz) though as Black has easy moves and it is hard to find accurate moves OTB as White, who has quite a weak king. The other important line is 15. h4 (Negi). Now Black must choose between 15...b4, which despite being the main line I don't like so much after seeing Negi's analysis and 15...h5, the ridiculous-looking move advocated by Jones, which is a lot sounder than it looks, but it is hard to know if it's completely sound (Ex: 16.gxh5...Nxh5 17. Rdg1!?).
Anyway, afer what I feel is a satisfactory presentation of the potential problems in the 11...Ne5 lines,
Is 11...Ne5 sound enough to play or should I fully take up the 11...Nxd4 Topalov Lines, after which it doesn't appear White has any line that gives a reasonable chance to "Blow Black off the board" and only has lines where White will have to be super accurate to reach a slightly-better ending (though not better enough to win against a decent defence, like any sound opening)?