Maugust789 P790 is built for distance and theoretically add height to hold greens but I found the P770's deliver much better green holding capability.
From what I've seen, some players have problems with distance control and not being able to hold greens with P790s and other 'player's distance' irons because they can't get enough spin on the ball - for others, that lower spin makes them an ideal fit (which suggests that going out and trying the different types of club available is a very good idea, or at least a way of avoiding a rather expensive mistake!)
(I haven't hit any of TaylorMade's recent irons, so not posting from personal experience. For what it's worth, I did try a few of Ping's range when I was fitted for my current i210s - hit a few with their player's distance model (the i500), and didn't really see any difference in performance compared to the i210.)