I looked into that type of setup, but Cat. 1 on ATV's and Garden tractor are just to big, also, the trailer type setups don't work as well as vehicle mounted units because all the weight is hanging behind the wheels on the trailer setup, that decreases the weight on the ball hitch and rear wheels of the ATV and decreases efficientcy of the operation and traction.
My 3-point setup adds a minimum of 200lbs of extra wheel weight, giving me LOTS of traction and downforce on the implement. trailer setups only provide enough downforce equal to the implement and trailer weight combined. a vehicle mounted 3-point offers vehicle weight plus 3-point system + implement weight.
For my example:
840lbs - My Polaris Sportsman weights
85 lbs - 3-point hitch setup
50-200lbs - my Implement of choice
250lbs - counter weights secured into front mounted receiver hitch.
1100-1300 lbs of digging/pulling down force on wheels.
Can't achieve that and still pull any ground engaging trailer implement that is mounted to any ATV or Garden Tractor. They look cool from the outside but as with large scale tractors you needs lots of weight on the pulling wheels to make it all work.
I will stick with my vehicle mounted system anyday.
My $.02 worth
TP