A friend recommended Tire Barn after my car developed a flat. I brought in the flat tire and they offered to patch it up, assuming that it was due to a hole rather than sidewall damage--and they let me watch while pointing out the problem areas. (By the way, they will check and repair flats for free if you mention that you're a student.) Bad news: the tire was irreparable and I was forced to buy new tires. Good news: I was already in the best store in town for tire products and services.
Customer service was very open and honest when showing me options. They understood my situation (poor, penniless student) and made recommendations accordingly.
If you purchase their tires, there is a warranty in addition to free rotations for the tires you bought. (For example, if you buy 2 tires and want all 4 rotated, they will charge you the adjusted cost of rotating 2 tires; if you buy all 4 tires from them, your rotation is totally free.) In order to uphold the warranty offer, you must be diligent about rotating your tires regularly--and Tire Barn WILL keep score. I've seen enraged customers having meltdowns in the lobby because their tires were bald and they weren't entitled to replacements (because they had never rotated the tires)--don't let this happen to you!
The staff works incredibly hard, but you can expect delays because the store is almost always swamped with cars. The wait in the morning (near opening) isn't so bad; in the afternoon, you can be in the shop for an hour or more. My advice is to drop off the car if you're not a fan of auto shop waiting rooms.