I have both the GO and the Altos2.. I love the both for different reasons.. I use my GO more than the Alto.
I disagree with pmrosie, in my experience the Go makes cutting faster for me, and as for the prep time it not time consuming at all. grab a scrap, pile them on, roll thru the GO.. Voila ! .. I have tons of pre-cuts waiting to be made into quilts.....And when im ready i grab the cuts i want and sew sew sew I go..