Yob,
I have recently changed from using American Ale strains to English for my Pale Ales and IPA's. Technically that would make them non American but they really do get a better beer, the English strains are more fruity and get more flavor from the hops coming through.
Stone brewery in the US use an English strain aswell as Brewdog in Denmark. I still will use the American strains and they too yield good results, if you haven't tried them yet on an IPA give one a crack with 002 or 007 and yes S04.
I would base the style on the hops used more than the yeast strain and US hops and English yeast I found to pair better for a hop forward beer like AIPA.