If you're concerned about a short bow "stacking" at a longer draw length, recurves are generally less apt to stack than longbows are. That's generally speaking, as some longbow designs are better than others about stacking.
I shoot 3 under and I've never had a bow tillered for 3 under and I haven't had any problems whatsoever.
Fastflite is faster than dacron and much stronger, but make sure the bow can handle it. I don't know that either is more accurate than the other one, though.
The top bows out there aren't always the most expensive. There are some fine bows that shoot great no matter what the price. I like Black Widows but I also like my rather moderately priced Dave Beeler custom bow too. Saw a beautiful Morrison Cheyenne today at a shoot for sale (see KY Rob here at the 'Gang for that one) and it was beautiful, to say the least. He offered it to me to test drive, but I new I shouldn't 'cause I'd be rurnt!
Too many great bows out there to try and narrow it down to just a few.