wow, theres a switch.
Alpha 1 = Lighter, faster, softer - but the base needs more attention and isn't as durable
Alpha 2 = SUPER durable, and a bit stiffer
when I say the bases need more attention, I mean they need to be waxed and scraped more often in order to keep them going fast, while the Alpha 2 can just use rub on wax and go, that's all. It is better to hot wax all skis, but some just can't use rub on. (Watch 4FRNT's Tech Talk on waxing and he'll tell you the difference).
My pick would be Alpha 2 just cause they're way more durable, and cheaper.