I switched from DSL to cable, and was happy. However, this is not necessarily due to factors inherent to the 2 technologies.
My Earthlink northern Illinois DSL was using garbage SBC twisted pair copper wiring, and was at the maximum allowed distance from the C.O. Also, there was a hierarchy of 3 different companies responsible for the service, so it was difficult to get quick resolutions of issues (they tended to blame each other). I was getting speeds barely above dial-up at the end.
My new Comcast cable modem service gives 4Mbps (more than the internet can handle), and has been beautiful. Only one company involved. However, I've heard that cable modem performance can be a function of number of users in the area, so perhaps my area infrastructure has relatively few users.