Sorry man, no disrespect to Stallone, or the first Escape Plan. The original was a pretty good movie, original, great protagonists, and it kept you on your toes with everything being the opposite of what you expect. Stallone and Schwarzenegger have an excellent, believable chemistry, and it's just a smart, overall enjoyable film.
If you agreed with, or plan on watching the sequel based on the successful attributes of the first one...
It's unimaginative, slow-paced, dull, the characters largely suck, even Stallone seemed to not have it all in him in this film. An even more pointless and unnecessary cameo by 50 Cent, which doesn't add anything to the movie, on top of characters you just don't care about or root for is exactly what's wrong with the film. On top of that, the action scenes leave something to be desired, the prison is WAY less advanced than the one on the boat, no guards for that brilliant human infiltration sequence in the first, just a random dark place with no identifiable or credible possibility of escape, but, somehow it all works out of course, leaving everything on something of a cliffhanger, but this is one where I'd rather just try to forget and move on with another plot. Overall, it lacks the charm and intelligence of the original, and the writing is so incredibly boring, I found myself looking at the run time to see how long it's been.
Don't waste your time with it, stick to the first, or if you want to watch a good, honorable sequel, try fuckin' "John Wick: Chapter 2", you won't be disappointed.