Thank you all for brain storm.
1) Would you prefer rotary cutter which has coated deck before painting ? For example cataphoresis coating. (just an idea, i haven't done research for cost)
I prefer paint, for best blend of durability and repair/touch up.
2) Rounded deck is a plus for choosen. How about rhino ? TW series of rhino don't have rounded deck, also they are not using structural member(tube) for strong rear side, but rhino sells a lot. Can we say rounded deck is not a must as long as you turn around trees etc. without problem?
Rounded back end fits shape of blade and makes it much easier to maneuver around obstacles.
3) Some models have a rear side rounded sheet metal guard. It bends and blocking discharge most of the time. What do you thing about rounded sheet metal guard ? I suppose chain is the only and best option.
I prefer chains or no guard. The solid guards get damaged immediately in my use.
4) I know you all want guide wheels, ıt might be good for grass or pasture areas. However, it would be a weak point for heavy duty, because of the roots and other tree parts. What do you think?
(This answer is for tail wheels. I don't favor front guide wheels) I always use tail wheels even when backing into heavy brush and trees. I even use the tail wheel to catch or trap trees, holding them in place as I back over them so they don't slide off to the side. Thin wire-like grass does more damage to the wheels (bearings) than trees do for me. The tail wheels can usually be removed with a few bolts anyway, so the option is already there for the minority who don't want them at times.