They are what they say they are, a discount shop of sorts for musicians. Focused mainly on amateur musicians, they have a decent selection of new and used electric guitars and basses. The focus more towards ibanez and danelectro in their selection.
The acoustic guitar room is pretty shoddy. They have a few quality guitars that they accepted for trade in usually and then way too many Johnson and other subpar branded guitars. Great for first guitars maybe, but one should really spend the money for a decent brand of guitar as it will hold some resale value while allowing the musician to advance.
They have a good selection of percussion stuff. Not really kits or anything, more just supplies. You can find the chord you need here, better to get it at this small shop than a megastore.
Trade in value is pretty good and the staff is super nice. In Phoenix you have to take what you can get in regards to music stores, this one is worth visiting.