I have used the KFI stealth winches on my machines for the past 4 years or so. The Stealth 4500 on my Yamaha Viking, 4500 on my Pioneer 1000, the 3000 on my Honda Rubicon, the 3500 on my Pioneer 500 and soon I will have the 4500 on my Pioneer 700.
They have been in the muck (on accident) and worked flawlessly afterwords.
I winched my Rubicon up some very steep and rocky terrain on the Hatfield McCoy system with no issue. And that one was running the winch over and over in order to get to the top safely.
I winched a Toyota Avalon out of my ditch during a "snow storm" . Used a couple of snatch blocks but it worked just fine.
Those are just a few times when I called on the KFI winch to help me out. So far, I haven't been let down.
For what it's worth, I also had very good experiences with the Viper Winches from Moto Alliance. I haven't owned as many of those but their customer service was pretty amazing. (Again, it's been a while since I've worked through Motoalliance so things could have changed)