I did this shop when it was with another company, paying the same. It wasn't a bad shop,although on the second one, they couldn't find the keys for the car I needed to test drive, so I had to wait a very long time while they located them. If all goes smoothly, you're probably looking at around 2 hours for on-site visit and report, plus any drive time. I've never done them with Maritz, but no problems with the shop being accepted.
This is definitely not the negotiation shops where you need to wrangle a price.
I do wonder how long the dealership keeps your info, though. One that I did before is open now, and it's been a little over two years since I did the shop. There are no other ones close enough to me anymore to make it worth it for $50.
I learn something new every day, but not everyday!
I've learned to never trust spell-check or my phone's auto-fill feature.