I have Yamaha Raptor 660. Has a White Bros pipe , jet kit runs pretty good kinda wish a would have held out for the 700 with the fuel injection but oh well, still pretty fast. I am looking at a utility/ 4x4 Quad not sure what kind yet.
We have two Arctic Cats. The wife's is a 400 4x auto; mine is a 650H1 4x auto. The day I took delivery of it I wanted to see what it would pull so I hooked a chain to my '05 Durango (while it was still hooked to the 16ft trailer); with the D in "N", the 650 moved both of em about 10 ft before I decided it wasn't good to push my luck. Both ATVs are mainly used for chores around our 17 acres.
I have an 05 Suzuki 700 FI King Quad w/ Pro Armor Guards and Bash Plate and a Mile Marker 2500# Winch. I also just got a 2008 Kawasaki 750 Teryx SxS. I have had several quads over the past 22 years. Warriors, Bayous, Wolverine 4x4 , 660 Grizzly, etc. My favorite all round atv was my 350 Wolverine. Perfect for rippin through the woods, hillclimbing etc. My 700 King Quad is a close second. I really liked my Grizzly but it had it's issues(vapor locking when hot and too dang top heavy). The 700 King handles great, and has a heck of a top end (73mph stock), just lacks a little on the bottom at times. The Teryx seems to be a really good ride, I am in process of widening my trails for it though. It is a lot of fun, but I got it to do more farm work. On the trails it puts you in the mind of a jeep or 4x4 truck in the way that it climbs, etc. I need to get a winch for the Teryx and new rubber for the King, and then I'll be set for a while.