As a guy that went to another clinic before signing up with Chip, here is my advice...
1) Go to Chip's website and fill out the form
2) Get your labs
3) Get the physical
4) Chip will call you once all has been submitted.
You are going to need labs and a physical regardless of the clinic you choose. You may as well get them done now. After everything is submitted, Chip will call and discuss your options. Use that conversation to see if you think there is a need to shop around. I'm sure you are going to find that Maximus is the only place to go.