Ive had AR5s AR6s and AR7s an here is a little summary:
the AR5s and the AR6s were most similar mailny because of the sidewall sandwhich construction all around. the thing with that though, is that after 4 seasons on my AR6s, they are now rockered skis. literally not much less rockered than my 09/10 Moment Bibbys. the edges on these skis though are great. they cant be tuned anymore, but there are literally 3 cracks and thats it. one of the cacks with a few more days of heavy riding may lead to a worse problem though - it looks like there may be a tear out on the way.
as for the AR7s, ive had 2 seasons on them and they are holding their camber-shape very well. a lot better tha the AR6s and ive probably skiied them harder. however, the edges are not as good, there are 7 edge cracks in about 1/3 the riding time that i had on the AR6s. and in the last few days, it looks like the base is seperating from one of the edges underfoot.
dont take this wrong, Armada is by far my favorite ski company. ive owned salomons, K2s, and moments recently, and im not saying they arent quality skis either, they most certaintly are. i snapped moments, salomons are pretty much garbage and K2s are a little heavy fro my taste (loved them though) so you cant go wrong with the AR7. get them!!!