A powder that doesn't get much mention for 10mm is BE-86. The Alliant book loads are very close to what I get from my G40. 1260fps from a 180gr Precision Delta with 8.5gr of BE-86 is nothing to sneeze at.
I haven't shot any of my Longshot loads, yet, but I have high hopes for that powder, as well as Shooters World Heavy Pistol.