I'm looking for a new set of tires for a Kawi 750 Brute Force... The tires on it now are ITP Mud Lite's that are shot... There's plenty of tread left on them, but there is a crack on the side wall where every outer lug meets the side wall.
Does anyone know anything about SunF, or MASSFX tires? I can get a pretty good deal on either brand on Ebay, but know nothing about them... Any input will be appreciated...

I don't think they are U.S. made, I just bought a set of Pit Bull Rockers , U.S. made, for my Viking, very happy with them. Like your avatar says..."take back America".

I don't know much about the brands/tires you listed
but there are a lot of good atv tires out there these days
top shelf brands, pit bulls, about the best I think for general all round goings
but they ain;t cheap
other good all round tires will be IMO
Bighorn's or bear claws, and I have loved my 589's been super durable and long lasting(5,000+ mile and still about 50% tread left)'
on a LARGER atv as you have I would stick to a MIN if a GOOD 6 ply tire
all maybe comes down to how and what you ride on though!

I have a friend who just put a set of the sunf tires on his Viking, they are 26" x 8, 10, 12 " wheels, they are 8 ply, decent tread, made over seas, he said it seemed to handle better then the bighorn maxxis he took off, fwiw