I have the same problems with dissconections and have heard that it happens if your line is idle for a few minutes, I got surftime 24/7 with Sniffout.com
I would play a lot more PBEM games but it just keeps dissconecting during the download of large files
If you can afford it then sign up for ADSL, I have, but they refuse to give you an installation date, gits.
Btw Demon does seem to have a very good reputation, but £40...