The Amperex 7316 is one of the best 12AU7s out there.
6SN7s are better than that though. 12AU7s, 6CG7s (also excellent) and 12BH7s are all based on 6SN7s (the 6CG7 and 12BH7 are literally 6SN7s in a miniature envelope; the 12AU7 is the same geometry but half-height), but for some reason the 6SN7 brings home the bacon the way the others don't.
6SN7s are better than that though. 12AU7s, 6CG7s (also excellent) and 12BH7s are all based on 6SN7s (the 6CG7 and 12BH7 are literally 6SN7s in a miniature envelope; the 12AU7 is the same geometry but half-height), but for some reason the 6SN7 brings home the bacon the way the others don't.