As far as interviews? If that is what you are asking they are night and day difference. PSA interview is a joke, I might have been asked a total of 10 questions. Compass has the 3 tests I am sure you know about, which takes about 3 hours, then HR with real life questions that can be a little difficult.

But to be fair it seems they have different philosophies screening. In the interview they told us PSA has a 20% fail rate, so it seems they are doing their screening during training. Compass has already screened you so they want you there and will do what they can to keep you there.