Cummins, Yeah thats the one I've been looking at since I blew the deal on the hustler. Down here in Md that unit with a 27hp kohler is $6995. for the 60". I'm sure it will handle your needs, I've seen that unit used commercially around here a few times , But most are still buying Emark here.
The new cub cadet Z-force looks like an acceptable option for a good home owner series,but I don't have enough info on those units as far as pump configuration, One or two pumps? The 50" is like $3999 I think?
There are more commercial quality units available ,but for my home owner dollars any thing more than that is overkill.
For my self I really like being out-side and a good unit like the gravely for the price will last me a life time, I hope /forums/images/graemlins/grin.gif, plus when I retire ,who knows I might even try a little mowing service or something since I'll have plenty of equipment buy then /forums/images/graemlins/laugh.gif