After having to intention to watch the show, my 6-year-old daughter got me watching it. At first I would watch to appease her, then I found myself liking some of the characters, and pretty much enjoying the slapstick humour aspect of the show.
This show does not take itself seriously. If it ever did, it would end up poking fun at itself.
Sure the acting isn't always great, but there is some growth to the characters, especially the Gustavo record producer character. He may yell at the boys, calling them his "dogs", but he's also shown as the fellow who writes their songs, and tries to make them sound good. His childhood was taken away from him by his mother who wanted him to be a master pianist. Kinda gives the character some background.
The music is what you'd expect, but then again you should think the same about the Monkees music. C'mon now, "Big Time Rush" is about as catchy as "We're the Monkees", especially for kids these days.
Each of the boys have their own special characteristics, and it would be interesting to see more story revolving around each character.
With the sound effects, music, some of the story lines and most of the humour, it's very much a live-action cartoon.
I don't go out of my way to watch the show, but enjoy watching it with my daughter.