Like alot of people, I used to use the Mach3Turbo. Its a great razor, and definetely would be my backup if I moved somewhere or was out of town and they didn't have Fusion heads. I tried the fusion after hearing some reviews on here and elsewhere and was blown away. It left my head super smooth and had minimal to no irritation and I only cut myself with it because I re-opened some cuts by my tempal from my Mach 3, which I admit was from my own carelessness.
So yes I am definetely a convert, although the price is crazy for cartridges,, its soooo worth it. I'll kill off my left over mach3 turbo heads eventually though.