Since I haven't read every single reply my thoughts have probably already been said.
I have a Featherweight for the awesome-est (is that a word?) straight stitch, ease of carrying to wherever, and also to hear the sound that the machine makes. It's like no other. I also have a 501 that will sew through ANYTHING and keep on going.
Like my GE steam iron from 1970, the old machines were built to last.
For the "fancy stuff" I love my Brother 820.