A great farm quad is a honda foreman, they last forever and are tuff not the smoothest on the trail cause of the solid rear axle but you'll be supprised where you can go with it. Those quads are damn near indestructable
Honda Rubicon is better, auto with a very good low gear, adjustable suspension out back , not as good as IRS but still beter than the foreman. I have owned and ridden thousands of kms on both machines and loved them both, never any problems.
I could never say anything bad about honda's... My old 300 honda was a absolute work horse I bought a Yamiha 450 kodiak and have been using it on my farm for 3 years. There is no stopping it and have had no problems... with it being automatic, i can pawn some of the work off on the kids and wife... This bike is awesone for trail riding, so smooth on any terain. i have never needed any more power even when i pull a trailer... my $0.02... Good luck
I will have to say Honda as well, I have had 2 Hondas a 350 with over 13,000 km. still going and a 500 Foreman with over 9000 km still going. agreed the ride has alot to be deisired but I have not been left stranded.