Lockdown is one of the best ones I've played in Vegas. Their Mob Boss room was my second escape room ever played, which we made it to the end, but chose the wrong culprit. This is about moderate difficulty.
My 21st ever escape room belongs to their Crazy Professor room, which we escaped with about 7 minutes to spare. This room is their hardest room, but very unique elements and puzzles.
Rooms should allow for at least three hints and 60 minutes of play, and good set design is a very nice bonus! Lockdown has achieved all three and I hope they keep their quality and standard high so that people get the best experience, since other rooms in Vegas are quite below par.
(I've done over 40 escape rooms thus far.)