I haven't heard the AP's, but did have the Green Mountain 1.5 in for an audition. Man are these great speakers. Completely coherent, wonderfully balanced, great top to bottom extension. The mid and tweeter "disappear" like great mini-monitors and offer a deep soundstage. Only reason I didn't buy them was because of the look of them. I listen in my living room and these things make a statement (size and appearance-wise) that was beyond what I was comfortable with in my room.
If I had a separate listening room, or listened in a basement or something, there's no question that I would have gotten them. But living in an apartment, and moving as frequently as I do, these speakers were just didn't match with my lifestyle.
FYI, when I auditioned them, I was using a Plinius amp. But I understand that they are quite tube friendly, too.
If you have the space, and don't mind the look of them, the GMAs are a definite audition.