You would think so (the “hard sell”), but we actually had very good experiences with them. When my S and D took their practice exams through the school, they followed up with a information evening to give scores and explain the college admissions process. Very informative, and the only “sell” was to give us their contact number if we had further questions. When they took the free sessions (which you can sign up for on their website, we got the results in the mail with no “hard sell” either — not even a phone call.
I highly recommend doing these practice tests because they give you the “whole experience” (sitting in a testing environment on a Saturday morning).
The have both ACT and SAT practice tests and the PRA (Prince Review Assessment) which is a hybrid of the two and suppose to help you decide which you might do better on.
Edit: BTW, these practice exams were the only prep my kids did…it was enough for them.