Michael Evans reviewed the 13th Age Escalation Edition for EN World, providing one of the most in-depth and crunchy-yet-concise examinations of the game to date. I encourage you to check out Part 1 and Part 2 of his review.
“As far as the Character Class design of 13th Age, I am quite impressed so far. I feel that the authors have managed to achieve a very positive blend of 3rd Edition and 4E concepts, but with some really interesting and thoughtful innovations to make the game more role-playing than roll-playing.”
“…[T]he ability of getting both d20 and 4E combats playable without a battle map is fairly impressive, and the FLWQ problem plaguing older D&D editions has been nicely solved here.”
“…I have to admit there is a lot to like about 13th Age, and I can see many 4E fans meeting Pathfinder/OGL fans on common ground with this game. While it has some mechanics which are reminiscent of both d20 and 4E, it strives very hard to favor story-telling and role-playing over that of rules crunching, and has some innovations to get players to develop strong and unique characters for a campaign. And it quite surprised me in finding ways to retain a decent amount of complexity in combat and game play without requiring maps and minis, and it still leaves flexibility for game masters to adjudicate and improvise.”