Eddie, the last four posts above are pure gold.
Let me add a few "nuggets"
If you will be on lumps like real tundra hummocks, the Desser 31" tires work a full hand above Airhawk 29x11-10's on Gar Aeros or 10x10 ABI hardware. The taller tire and sidewall flex allows that, yet with no sidehilling issues as Algonquin feared above. I have run Airhawks and Desser 31's at 9 psi without spinning on rim. Both were glued to the rim in the vertical portion of the tire rim interface. All on early 180's at 2950 gross weight and also empty.
8.50-10's on Gar Aeros have spun a bit at 12 psi on me, not sure why. Poor glue job??? All these setups have been with max performance braking for many ops cycles.
8.50x6 work just fine on hard surfaces with some roughness, but beat the airplane unless you have early gear legs, which are a good choice for a light airplane.
wide tailwheel fork is important for float!
I lost 11 mph going from 8.0x6 and stock tailwheel to Airhawks and wide tailfork with glider rib on my 185.
Desser 31" on 10x10 ABI field approval is in the mix for my 185 and should be complete before I leave Anc for flying season in Katmai Park, where tundra ops are what I subject my bird to on days off.
For my money, 29" Alaskan Bushwheels or Baby Bushwheel handmade tires won't do. I have run them a little and been around them, but never saw them doing what I do every day off with Desser or Airhawk and glider rib. Also, sidehill with 29" Bushwheels on a heavy plane seems scary. One sourdough told me "...oh, you are GONNA THINK it will roll off the rim!...". Yep, I think it will.