I've had DSL/Cable/Fractional T1.
My max speed on my DSL was 416kbps, up and down. This one was costing me 60 a month through Northpoint (Bankrupt). Never had a drop in speed when it was online. I live about 3 miles from the phone company. My DSL line had considearble more downtime than my cable modem has ever seen.
My max speed on my cable modem is 4+Mbps on the download side, but they cap the upload at 785kbps. During peak hours it will drop to the lowest of 785kbp on the download side. This one cost 42 a month through Earthlink. I live about a mile from the cable company.
At work we have a fractional T1. I would be lucky to get to 200kbps. ISP really screw with commercial customers. Then again when you have 100+ people online it tends to have an effect.
The difference in the price was mainly my DSL was a Satic IP. I used to run a server with it. The cable is a Dynamic IP.
As far as I remember the reason the DSL and the telephone don't clash is because of frequency separation.
Just my experience. Yours may vary depending on location.
