I signed up for this late last year and recently renewed for this season.
First off, I love the fact that they archived all the 2008 games and allow you to watch them in addition to all of this year's games. I typically go out to a bar to watch the Bills live, but this allows me to watch other games that I missed or maybe even re-watch a Bills game if I missed something. The quality of the video is absolutely awesome. It can get grainy at times (usually when your video is just starting or if you jump to a new spot,) but usually is damn close to the "HD-quality" that they state on the site. One drawback is the quality of the multiple game viewing. The games that you don't have pulled up on the main screen are WAY to small to watch. You can basically see who's playing the game and that's it. Hopefully, they can improve it.
Overall, it's worth the price to me and I recommend it. If you can stand not watching the game live and waiting 'til midnight EST, then it's highly worth it.