This literally took me 3 minutes to put together and attach to the crib. I was worried it wouldn't fit on the crib based on other reviews, but the way the attachment piece is designed, it easily fit between slats and is secured safely and tightly. I am glad I ended up buying this 34-inch option over some of the shorter ones, I can't imagine it being any lower and being safely out of baby's reach. This one is perfect height.
The music box is pleasant and rotates nice and slowly and is easy to unhook and replace with a different music box if you want more variety. The white plastic doesn't really match anything else in my nursery so I ordered a sleeve to cover the arm (which sadly cost more than the crib arm itself!).