Thorny, but better than Comcast...
Cox is usually the fairest of the companies in the US, from what I've read. They have pretty good service and speed. Comcast also has great speed, but shit service. In principal I like what Cox is doing, but it still may not be entirely fair. The fairest approach would seem to be to take the current available bandwidth, divide it by the number of "active" users, then give everyone their fair chunk to with with as they please. But that is easier said than done (i.e. how the hell do you figure out what an "active" user is with POP clients constantly polling for email)
I've hedged my bets now. I have Comcast and Qwest, and a dual-wan Netgear router to route traffic through the best network available. Its still not a panacea: Comcast is fast with low ping and fat upstream, but their billing department is so idiotic you stand a good chance of having them cut off your cable for a bill they already auto-charged your credit card.
Qwest sells 20mb service, but after contention, that usually works out to 768down/256up during peak times, but hell when your DSL goes down they seem to be able to fix it while you are still on the phone, unlike cable. Once I had my cable go out for a week, and Comcast said that corporate couldn't talk to local, and that they had no idea when the trucks would go out, and that they could tell me no more. I spent a whole day on the phone, beating the hell out of the reps, and I gotta tell you, they were telling the truth. They had no freaking clue about the status of the repairs, and they couldn't even contact the local branches themselves.
Fuck 'em both. I hope O'Bama's damned broadband give away forces these companies to sell something that isn't shit, and until then, I guess I have to pay for them both in the hopes that at least one will be up 99.9% of the time. Wheres the "I want my money back" icon?