I'll go three stars. For Phoenix, it's good to have some of these around to keep a large selection of instruments floating around the valley.
Yes, GC is the devil, who puts little guys out of biz while bringing up the douche quality of musicians everywhere. They have annoying sales people who are dangerously uninformed while being horribly brash. They have plenty of crap product and they will sell it to you with glee.
There are a few saving graces. 1) I play acoustic guitars. They have a nice selection at several price points which aren't all that horribly priced. You can play the $3k Martins without being bugged and can stay for hours (sometimes a bad thing when old farts decide to play concerts loudly) 2) The sales people are dying to make a sale. If you are going to spend money, they will bargain, just have to push. 3) If you buy used stuff from them from a brand they don't really carry, it may be priced to get out the door. They are afraid they won't sell the stuff and it will just take up space.
I hate guitar center except for the acoustic room. There's always someone playing everything too loud. The staff will always show off on your interest before they let you play it. They are the Walmart of music.