Langdon will work on your Sig just as fast as he will anything else... In fact he won his last competitions with a P220ST.
92 vs. 226: Tough call if you are talking about 9mm... we are talking about two of my most favorite guns here. I love the ergonomics and functionallity of both. I suppose if I had to pick one, it would be the 226, since I like everything about it just a little bit better: ergonomics, lack of external safety, closed top slide, decocker...
If we are talking .40's, I'd take the 226 in a second, as the .40 version was better redesigned to handle the hot loads than was the 96. Heavier slide, spring, lockup, etc.