The difference in weight between an 8274 and M12K is 26 lbs.
Any winch is going to add weight to the front, but the ability to pull youself and others out of an unfortunate situation is well worth it.
M12000 is WAY overkill for an 80. I had an M8000 on my Rover (just as heavy as a built 80) and with the proper gear you can get yourself out of any situation in my opinion.
The M12000 weighs a wopping 136lbs. My XD9000 weighs in at 78lbs. Throw some synthetic on there and its almsot half the weight of that M12.
What advantage does the M12 have? maybe pulling yourself out without using a snatch block i guess.... I keep two snatch blocks in my gear bag. I'll stick with the snatch blocks and a light weight winch VS a fat turd (overkill) of a winch on the front.