Getting out from Comcast in any way possible is a win in my books. Fiber won't hurt you either.
Just make sure its fiber all the way to your house. ATT tried selling me "fiber", only to find out fiber only went to the closest routing box. Copper the rest of the way... Chumps.
The last mile tech (copper vs. fiber) doesn't really matter. Using existing copper for the last mile is significantly
cheaper than retrofitting fiber to every house. With VDSL the distance to the VRAD is all that matters. Around here, there's a VRAD at the entrance to most subdivisions, so it's pretty rare to be more than 3000 feet from one. Granted, they won't even offer you service if you are.
Ironically, with U-Verse, FTTN (copper last mile) is a better product. Because FTTP (fiber last mile) is more rare, something like 4-6% of the total network, certain upgrades come to us later. Some changes, like 24 meg internet service, are completely unavailable. I have FTTP currently, and had FTTN before I moved here. I'd actually rather have the FTTN service, as I had less problems with it. Granted, I do like pings in the 20s...
That said, Centurylink looks to be FTTN with VDSL over copper for the last mile as well. So long as your wire distance is in the optimal range to your VRAD (between 1000 and 3000 feet), you'll be fine.