I wear a 41 in the Tech, and bought a 41 in the ice. I could barely get my feet in them at all, so I have since removed the insole and use a thinner sock. I wish I bought a 42, but then who knows, they might have been a bit sloppy, and since they don't make 1/2 sizes no 41.5 for me. I would recommend trying them on if you can first, or if you are shooting for only one pair, go up to a 44. IMHO they run narrow and small, they are a bitch to get into but once on, fit like a rock shoe. Also, fining hardware for the bolt on crampons (I went with BD) was a pain in the ass, but I found bolts that worked for me after about an hour at the massive hardware store and a drop of locktight.
I don't know about the fruit boots but the Phantom Tech fit the exact same sizing as the Rebel Pro GTX.
*Edit. After looking at the Scarpa site, it's evident that the Rebel Ice (AI) are built on a different last than the Rebel Pro (NAG). Which is the same last as the Phantom Tech.