The best has to be the A500, it's the sweet spot for classic software and was my first Amiga and the most popular by far.
My favourite would be the A1200, like an A500 but with (a bit) more grunt. The only pity is, its potential was never really realized with software being slightly tweaked rehashes of A500 titles and many classic games being non-compatable.
WinUAE is now my favourite (unofficial) Amiga model. :-P
