This is a kids game and is ridiculously easy to finish. But they have a platinum trophy! This is the easiest platinum I've made, took me about 3.5 hrs, one playthrough and no revisits.
Game play is quite straight forward, you just need to navigate around doing what they say. Boss fights are really really easy. Controls were OK, but I had minor trouble controlling Megamind while jumping on floating crates. Also felt that the viewing angle was a bit awkward at times. But for that, there is nothing bad about this game; although it is just not worth paying for and owning. Renting would be the best option.
If you are just looking for a few hours of fun or for a trouble-free platinum trophy, you can't ask for a better deal. I have to say that gamefly's turnaround time of 7-8 days is a lot, given that you play this game only for a few hours. A friend of mine rented it from Redbox for 2 bucks and I would've done the same if I had known ... and used gamefly for a different game.