It basically comes down to if you want to work the ball or not.  The ap2 have been made a little more forgiving for chunky shots but you still need to be a good ball striker to hit them well.  The ap1 fly straighter and are more forgiving over all.

If your reason for a 15 handicap is other than iron play, should be no problem. 

The AP1s are pretty easy to hit.  Keep in mind their lofts are 2* stronger than AP2s (5 yard approx distance diff).   If your goal is better ball striking and shaping, AP2 is the way.  I have AP1s and really like the feel; however, didn't find much of a problem with a demo AP2.

Just got my new custom fitted AP2 irons today. They are like a hot knife through butter.Very smooth, easy to hit and forgiving while still providing great workability. This is one sexy club!