The only thing about cable is them over-taxing the node in your area. They tell you those high speeds upfront but when you go to reality and try to download you realize that it is just not so.
I would go with whichever is most economical for you. Try one out, providing their is no contractual obligation, and if you don't like it, try the other.. Or try both, and drop the one you don't like or that doesn't meet your expectations.
I have had both, and honestly can't tell the difference, other than the upload speed of cable generally being much faster, but that all depends on the node and area in which you live. If there are hundreds of people on the same node, then your download and upload will creep to a crawl at peak hours..
Notice also that they don't guarantee you'll get those fast connections all the time...
They told me generally 1.5 DL and 256 up.
Generally being the key word... What does generally mean. Does generally mean that when no one else is on the line you will get those speeds? LOL

It will be faster than your dialup but soon you will adjust and want faster speeds.. as I have done. I am now looking at the possibility of a 12Mbit service to increase the speed a notch or two.
I don't think the US has those faster DSL services like here in Japan. I believe we have in larger cities anyway up to a 100Mbit service provided over DSL... I am dreaming about that..
let us know what you ultimately decide.
BB