Well Warrior, you're right - there are pros and cons - to both machines. I absolutely love my Turf Tigers. I do believe they are without equal for everyday mowing. Solid build, excellent design, the most versatile deck in the industry - these machines were made for the commercial world of mowing. But they do have flaws - the small fuel tank, no EFI option over 30hp (though, from what I understand, that will be corrected next year), and the ride. The ride isn't terrible. It's actually what I'd call typical for a full size zero. But you're coming from a full suspension mower and I would imagine that it would be a difficult transition to a rigid frame mower. From everything I've read, the Ferris 3100 is a solid commercial unit and it's deck is pretty much a copy of the Scag Velocity Plus deck. I'd spend quite a bit of time running demos before I made that leap... the grass is always greener on the other side of the fence.
As I said, I love my Turf Tigers... wouldn't trade them for anything. But I am planning on running demos on the Ferris 3100 either this fall or next spring because I do have interest in the Ferris as a specialty mower for rough properties.