E+ is much better than coach on American. The downside is not all United flights have E+ - there are a LOT of old United Shuttle planes still around - was on one last week that still had the Shuttle logo on it, and all the seats are the crammed-full coach seats. Don't be confused by "Premiere Zone" and Economy Plus, they are not the same. The premiere zone is just the first few rows of coach which may or may not be Economy Plus.

Before the demise of United Shuttle I rarely saw a plane that didn't have the E+ seating, now I see 'em all the time, or at least a lot more than I would like to see them.

If your boarding card says "Economy Plus" than you have it and enjoy the extra legroom, it is more than MRTC on AA.