If I ever lived in an area where my only option was Comcast, I'd get a business line from day one. I average 250GB every week, much less every MONTH. Luckily I live in an area that gets Charter, and gets it rock solid with great speeds all the time. No caps, no throttling, the only downside being the upload speeds aren't amazing. Bonded connections will fix that with time.
But seriously, fuck comcast. They're inconsistent as hell too. People talk about going over every month and never hearing a word, while others download 251 and get a bitch fit thrown at them.