Here in the States, I use a sled for game shot in the snow, and a cart like the one posted above for dry ground. I also own the capstun I attached a photo of made by Simpson. It attaches to chainsaws if you have one, so you can buy it without the motor. It has been a lifesaver in a few canyons with thick timber .
This is the very one I have myself.
I imported it in 2011 from the company.
I still see them now and again on Ebay.com The pound has been doing not too bad the last while against the dollar so possibly a good time to buy.
You can also find winches on some of the Arborist sites, both from suppliers and second hand.
I also a couple of years ago bought a Kawasaki Berger and Schroter from a member on here. My pal currently has it on loan, it had an adapter plate fitted by the lad I bought it from but when the company brought out the additional bracket and ring, I bought and fitted that to it.
The Honda is a great machine, although I looked at the chainsaw winch attachment initially, I struggled with finding how you would keep a constant throttle. Perhaps there are attachments for this but at the time I couldn't find anything.
The Honda engine has the advantage of being able to run upside down or whichever way it is sitting as it has an oil spray (not sure if that is the correct term) system inside it. According to the spiel from Honda anyway.
I fitted a bracket to the front of the quad and you have it with you whenever you need it, carry the wire strop as well and you can detach the winch and use it away from the bike for more difficult to access areas.
Another way you can use the winch in really rough terrain is to strop the beast to the winch and work the beast up through the snags as you go, as that saves the possibility of getting the beast totally stuck.
I wouldn't be without it and although as mentioned in my earlier post, it is not fast but what price to save your back and effort.