Good Rigging Control System (GRCS)
We had huge problem finding a tree-mounted winch that could do most of the tasks expected from a single unit; we appreciate the initial cost involved in purchasing a winch of any description, so it's important to get it right first time.
We
feel that the Good Rigging Control System (GRCS)
is the right tool for the job.
The GRCS is a device that provides mechanical advantage for the operator
to lift/pull 2000lbs single-handed, to retrieve slack on the rope, lock
off the rigging line and to lower loads under control.
This is achieved by one of the most powerful winches in the boating world, the Harken 2-speed self-trailing rope winch which will take a 5/8" diameter rope.
Crank the handle clockwise you have a 4:1 advantage, anticlockwise
it gives you a 14:1 advantage; this would enable you to raise a large
limb away from the roof of a house for example, and combined with the
self-trailing feature you eliminate the need for a second person to
hold the rope tension. 
Also included in the system is a 4" friction bollard which can be used instead of the winch, and not one single component weighs more than 37lbs so set-up is quick and easy.
You could also add an optional drill driver to power the winch with a cordless drill or even fit a mounting plate to a vehicle - this is such a versatile tool.
