We've used the Exxon at Waugh Chapel a few times now for various minor repairs and have always had a good experience with them. We had to have a couple of items fixed on one of our cars before it would pass for Maryland inspection and the folks at Waugh Chapel's Exxon were great about getting it done and charging a reasonable fee. We have had at least one occasion where the vehicle needed rather immediate work and the mechanics were willing to have us just drop it off at their lot in the evening and they got back to us the next day. We had a rear light that appeared to have electrical issues that they were to have fixed so we could have our Maryland inspection approved. They took care of the light and didn't give us any hassle.
If you don't have a smaller mechanic shop to go to, this one will still give you a decent deal.