Yes, FD gets a bad rap because of that and because you have to modify them to get to iris control. But for adapter use they're simply perfect and IMO is one of the best bang for the buck choices out there.
Ditto. Don't really know why so many people go Nikon. Sure, one can use those lenses on SLR body, but people will keep on asking what the purpose of those strange gear rings is
The advantage of Nikon mount is that you can get really nice fast zooms. All but a few Canon FD zooms suck.
I spent less than $700 on this set of nice FD primes (all in excellent condition, all Canon):
24 F2.8
28 F2.8
35 F2.0
50 F1.4
85 F1.8
135 F2.0
Sure, they're not Zeiss glass, but they are really good and very well color-matched.