It's slow and annoying, but the actual dial-up part of it seems pretty solid, and it's ever so much less stressful to not be using someone else's phone line. The mere fact that I can leave it connected in the background rather than having to log on, grab stuff and log off as quickly as possible is a big difference.

Thanks for the suggestion about twitter mobile -- I couldn't get it to work, but that's almost certainly because I have NoScript running and they weren't playing nicely together. I'll try setting it up when I'm at home for future use.