This game is great. and the reason this should be chosen over Dark Legacy is because Dark Legacy has terrible music quality. It's inconsistent, crunchy, clips, the instruments are constantly fighting to be heard, there's barely a tune or rhythm or beat in some tracks just noise it's a MESS. But N64 Legends? Baby that's sweet sweet quality right there.
Go listen to Castle Courtyard for each OST, then tell me which you think is better--it's N64's version--while I appreciate DarkLegacy's attempt at including a Spanish guitar the whole track sucks. And if you think the DL version is better, you're wrong. Flat out. Don't get me started on Desecrated Temple.
@iamfuturetrunks here is also SPOT ON with the differences. Legends is a gold standard for Gauntlet IMO