I bought this with a bunch of other cubes, looking to "update" my collection, and I thought the 5x5 would be the smallest upgrade out of them all (I was using an MGC before this). Boy was I wrong; this thing blew my old main out of the water. Both the inner and outer layers are really fast out of the box, and the speed between them is pretty even. I also find that even with the really fast speed, the strong magnets keep it controllable and stable.
My only gripe with this is the very difficult to remove center cap design; the size might be a detractor, but I find it's quite comfortable, especially with how wide the outer layers are.
But yeah, really good cube for this price range, highly recommend.