RE: First ATV choice?
Kodiak, as mentioned the size can be a draw back for the larger cc'd machines and many will never harness the power to warrant the larger stature. I have had the chance to trial the 05' 450 Kodiak and well I must say it impressed me so much I deceided to purchase the bike. Last week we encountered a very wet moose hunting trip and it never let me down. In fact in more than one occasion the diff lock feature it had over the other 2 bikes on the trip proved valuable. In one such example we were dragging back a bull moose whole to camp, the original bike (manually 350) could not gain enough traction to pull the moose up the steep incline due to the limited slip diff. I hooked onto the moose and walked away with it by using my low range and diff lock. This is one thing I really like about the kodiak selectable between 2wd/4wd limited slip & Diff lock depending on the conditions. The other thing I have found is it has lots of grunt in low for heavy work and EBS is among the best in the industry...I hardly use the brakes. Ride and handling is great. Did take me awhile to get use to the IRS but I have found it stays well planted and improves the ride greatly over SRA. I haven't encountered any towing issues as a result of the IRS, have towed trailer weights above 1000lbs and dragged dead of pretty decent proportions.
Others I would consider are the Honda Rubicon or Honda Foreman.
Make sure you consider a 2500lb winch and look at putting on a set of good aftermarket tires in lieu of the factory(if you plan to go into rough terrain).
Best of luck