Lewis Grabban is a very good striker at championship level. Haven't seen much of Dawson in the Championship but he'll had a bit of experience to their backline and is probably decent enough at that level. Colback is trash but might do something with the drop in level? Not really sure. Pantillimon is a bit meh but again .. decent enough at that level, and then Jack Robinson had a really good season at QPR. At least when I watched them he seemed to play well and the one QPR fan I know was very annoyed he left on a free after nailing down a place there.
Not sure about the arrivals from Benfica, but I imagine (like the players who came to Wolves) they'll do well. Not going to pretend I've watched them play but they should be better technically than the vast majority of players in the league. Overall they could do pretty well, lots of solid players who are proven at championship level, complimented by a few who could potentially look a step above. Will be keeping an eye on them.