As i have posted in other threads, we used and were very happy with COST LESS Driveways. They did the driveway, walkway, garage and lanai. It was $1.10 / square foot. It was done in Feb/Mar of 2010. The garage floor still looks like the day it was done and this garage floor takes some pretty good abuse from jacks, dropped tools, etc....
I cannot speak to expoxy versus stain, they used stain and I was very impressed with the process and the way after prep the concrete sucked in the stain. If I went with epoxy, I would certainly like to ask some contractors who have had to do this for years. I am not saying I do not trust saleman, but I ......
Good luck!!