I had a 6000lb Ramsey on my 89 Bronco for 10 years. Stalled more times than I can count....BUT, that and a shovel always got me out. I had a m12000 Warn on my 01 F250 Crew Cab Powerstroke (8000lbs) and I stalled that many times as well, but same story, that and a shovel or a snatchblock always got me home.
That said, I'm running a 17,000lb winch on my 98 Suburban now. Haven't stalled it yet....happy about that. Buy the most your budget allows. Anything is better than nothing.
1998 K2500 Suburban, 9" lift, 37" Baja TA's, 4.56's, 16k Winch, Lots of mods