I play on dial-up with no issues at all. Well, actually 1/2 speed dial-up. My computer is capable of 56K dial-up, but since the area I live in is farm country with crappy old phone lines, the phone company limits me to 28K dial-up.
I generally connect at 26.6K. I had to disable the "Data compression" boxes in my settings, and I do run on a second configuration with only 14 processes running while I play AH. The people I wing up with fly on more modern connections, but we're unable to detect any differences in performance.
Don't let the dial-up thing stop you...
MtnMan