Accuracy Unlimited, Glenn Custom: what ever the name, Frank Glenn Master Gunsmith is a great find. I have used a number of gunsmiths in the Phoenix valley with varying levels of satisfaction. Typical turn around for other shops has been two to six weeks. Most were closer to six weeks. Quality of work varies from average to unacceptable from other gunsmiths. Frank Glenn is the only gunsmith I can recommend.
Frank is a competition shooter that has built competition guns for some of the best professional marksman in the country. I don't have any super custom guns, but minor work I need done to my home defense and daily carry guns has been done to the same quality as the pro's get. Also impressive is the advice he gives while I waited for new pistol sights to be installed. Wait for sights to be installed? NOBODY installs gun sights while you wait that I have found except Frank. And, I have a list of drills to work on to help with gun handling issues he diagnosed while visiting while I watched him install the last set of night sights. Most shops the customer never sees the gunsmith much less have a conversation about gun handling.
Customers get to stand bench side in his impressive machine shop while he works. His web site lists the cost of standard upgrades and repairs. Be sure to ask about anything not listed. Frank can repair, modify or fabricate just about anything.
The only negative thing I can think of is there is only one Frank Glenn. He answers email and the phone if in the shop. Service is by appointment. Be sure to call before dropping by. He has little patience with people that bring loaded guns into the shop. Be sure to unload the gun you want serviced before entering.