I did one shop for them a few years ago and it was okay. I did get paid, I received a check about 90 days after the shop was completed. I found their reporting form to be kind of a pain, plus I had to print the form, write my notes and send them a copy of my handwritten notes as well as complete the online report. Way too much work, so I haven't been enthusiastic about another shop and haven't seen anything I was interested in doing with them.
Based on my experience, I would say you won't be paid until mid- to late-May for a shop done 2/15.