I've purchased two different all-city brand bikes from the shop new, and taken a few other bikes in for service and always been totally satisfied with the quality of work that they have done.
Thick bikes carries a lot of products geared towards commuters and is less aimed towards high end road stuff. You'll see a lot of steel bikes, some aluminum frames, and not much carbon fiber. Most of the people in the shop ride mountain bikes, so they also tend to have a good amount of mountain bike and cyclocross gear as well. I do a lot of bike maintinance myself, and when I go there for parts and other gear, they usually have what I need in stock, which is a huge plus for me.
They have a stock of refurbished used bikes at really reasonable prices in their basement which you might not notice when you head in to the shop. It's a really good alternative to buying a used bike elsewhere since you know it's already been looked over and tuned up by a reputable shop.