I used to have cable, and I used to have DSL. Both were about equal. I now have dial-up (don't flame yet). It was a very hard withdraw. I have dial-up because I pay $10 a month on top of my local phone bill of $18 a month local calls only (central Florida). I use my cell phone for long distance and have a good bit of minutes from the old AT&T so Cingular cannot change that (and my cell is deductable on my 1099). Cable tv is included in my rent.
Between the dial-up, cell phone, home phone I pay on average $80 per month. I switched to dial-up to save expenses, and it does suit my needs currently. High speed is certainly MUCH better, the only thing I am missing now is the downloading of songs and pictures take a while to download.
If you are budgeting, I would try to stick to dial-up, and when you get a roommate, go halves on the high speed.
Cfrost, are you going to a flight school? Can you call ahead and have them check the bulletin board for someone who is currently looking for a roommate? You may not have to commit to a lease, perhaps month-to-month, and while you are there initially you can check out other living options.