I have skied both and would go for the infamous every time. The future spins were ok, allot better then the after band and TC, but they still could not really hole an edge that well. They were super soft too in the tip and tail, which verged on being too soft to even be playfull. I did try them in a 171 though when normally id ride 181, so a bigger size may help.
The imafamous in comparison felt like a ski you could really haul on yet still ride it slower and jib in the park. The flex was much more consistent, still soft but would hold an edge underfoot. I just wrote a review in a second thread, all about it.
So for me, defiantly Infamous. The future spin is lines best park ski next season IMO, but its not as good as the offerings from other brands for next year.