No surprise For me, the thing that chased me away from DSL was AT&T's attitude.
(this was a few years ago)
I called AT&T and asked about their DSL service. When I asked them what speeds are available, I was told "up to 8mbps" and "up to 6mbps".
Hearing the "up to" weasel words, I asked if they could tell me before I sign up what speed I could expect, and they answered "no", that I would have to sign up for the service (one year contract, minimum) and then see what speed I got.
So I asked if I sign up for the "up to 8mbps" service, and I get less than 6mbps, would I have to pay for the "up to 8mpbs" service or would I fall back to paying for the "up to 6mbps" service.
I was told that since I signed up for the "up to 8mbps" service, I would have to pay for that level of service for the length of the contract.
At that point, I moved over to Comcast HSI.