This location is always busy and unkempt and dirty. I usually plan to wait for 15 minutes when I go here. It's also very hard to find, so familiarize yourself with a map (or use google maps every time like I do)
I try to use the location on Scottsdale & Williams as much as possible for an overall better experience. It's located here:
7339 E Williams Dr
Scottsdale, AZ 85255