Most of the pushing I've done has been in 35mm. For my uses Delta 400 in either d-76 or XTol turned out nice really nice.
TriX has been similarly to my liking.
I must say though that more than film choice subject matter has been the biggest issue. If the scene has lots of dark area any of the 400 and faster films work fine for me. When the subject matter is lighter I like Delta 400 more.