Quoted from Jediturtle:

I have owned both. GOTG left very quickly, while TMNT will be a long term keeper. GOTG was one of my biggest disappointments. Yes, it's a solid game, but it's just so damn generic. Almost everything about that game was recycled from a different, better game. The playfield has been done (better) a million times before. It is almost literally a combination of Metallica and Iron Man. Combine that with a basic code structure that has also been done a million times before, and it just has a "been there done that" feeling. I try not to criticize designers too much, but honestly GOTG is probably the laziest, most phoned in machine ever made. Perfect example of how lazy it is...Cherry Bomb. A mid-point mini-wizard mode that was tacked in with absolutely no theming other than playing a song that played in the movie. They didn't even bother to put any sort of video or movie tie-in. Just some cherries and bombs because those are words from the song. Ugg. So much awesome stuff in the movie...and that is what they decided to do with that mode. Come on...at least have the Milano flying around or something...anything. It's a perfect license, and a machine I was super excited for. Yeah, it's a decent game, but the games it recycles from are better. Just a damn shame all around.
TMNT on the other hand...complete opposite. The layout and code are both unique and loads of fun. Yes, there are bits and pieces of design cues from games like Tron and X-Men...but nothing overt and it is definitely it's own thing. Same with the code. Yes, it shows a bit of the same signature of SW and GoT with the choices, mode strategies, and hurry-up based side goals, but it is definitely it's own game 100%. Plus there are so many ways to play, it will not get old for a very long time. Go for modes hoping to get to Team-up and then Final Battle (not to mention the strategy of which modes to bring in to TU). Go for training to level up and try to get to pizza party. Concentrate just on the various hurry-ups. Put together the perfect combination of toppings before starting Pizza multi. Try to do it all for Cowabunga (lol Good Luck!). Try Final Battle Challenge and see how well you can do. Try a speedrun completely separate from the rest of the game with Half Shell Challenge. Have friends over? Sure you can just compete as usual, or you can team up in co-op, or even gang up on each other in a 3-on-1 or 2-on-2 battle. So many ways to play. GOTG? Slog through the generic modes, use the generic multiballs to help (props to Groot's moving mouth on the super though), drop some cherry bombs for no apparent reason, then Immolation Initiative and Save Xander (which I admit are pretty awesome). At least you can choose your mode order...but there isn't much strategy in that since they do not mean anything later.
Playing GOTG I can't help but think this is just a IronTallica ripoff with a crappier version of Star Trek's rules. Playing TMNT I am playing something completely unique while still feeling like a Borg/Dwight game. All that said...I kind of have an urge to play GOTG right now, LOL. Will I be shocked if I ever own one again? Not really. Like I said it's a solid game...just not unique in any way. Could I ever see giving up TMNT for it? Not in a million years.