IRS vs SRA has nothing to do with pulling/climbing power its just that a SRA carries zero trailer tongue weight on it,s suspension.
Low Range and AWD are the two things that helps when pulling and climbing.
My SP500 can climb hills my 450 Foreman could never do . 4 wheels just pull harder than 3 can.

 

Do NOT get a IRS if you are working with it and such... its not a good idea to be towing stuff around with them squatting the suspension all day and honestly they just feel awkward working. I've used both SRA all day long for working. Not to mention i wouldnt really want a CVT tranny for any amount of real hard work.

The only real options here would be a honda rubicon,foreman, or big bear.

I would ideally go for the rubicon but its more money than the others, and the big bear is only a 400.

The foreman is great for work the first gear is plenty low for towing anything I would go for the foot shift model.. I actually own ES model hondas and havent had any trouble but i know people do have troubles with the ES sometimes..

The rubicon is a beast for working in low range the thing will hold you back at 1mph going down a hill. The newer models have disc brakes in the front, they are probably the most reliable atv being built today. My friend has one and he trail rides the hell out of it, beats the living snot out of it,this guy doesnt even believe in oil changes or cleaning an air filter and he's got like 6k miles on this thing.

Ohhh and as far as a brute force SRA please for love of god don't buy one of those.. they will make you hate ATVs there reliability is TERRIBLE!!!!!!! I cant even imagine if you worked it The fan would never stop running OMG would be a nightmare!!

it really depends on how much working you are really gonna do... if your only using the atv a little bit probably anything will do.. but if your serious about pulling logs and towing a sprayer around ALOT then you need to get something reliable...

 

The issue everyone raises with the IRS is the squat when loaded. I've pulled the trailer I described many times with my 350 lbs., and a passenger in the 200 lb. range. I only have the shocks set on the 2nd of 5 clicks adjustment. I've even had an industrial sized wood chipper that my buddies Chevy 1500 or my GMC 2500 with rear locker could not pull up a hill with wet grass. We hooked it up to my X2 and, yes, it did squat, but still had more clearance than a comparable straight axle. 6 guys planned to push the chipper while I pulled. Put it in AWD low and hit the throttle. I left them all behind and easily pulled it up a 20 degree slope and onto a level area. Would I recommend pulling a 2000 lb. + chipper for any real length of time? No, but it did it without a complaint.

Another thing to think about is the braking on the machine. If you are going down a hill with that kind of load pushing you from behind I would recommend getting a machine with 4 wheel disks if you can find one. I know my 2006 has them but I'm not sure about models after that year. I can modulate the braking and keep under control going down a hill by "tapping" the brake lever like you would on a car with no anti-lock brakes.

I had one more thought. The Polaris ATP 500HO. It is a carb. model with a dump bed and a solid axle. It has an honest 400 lb. rating in the rear. My son had one but the ride was harsh. He sold it and got his Renegade which is super sporty.

This picture shows the trailer that we use to pull the wood down. We usually heap it up as high as we can. My guess is around 700-800 lbs. or more when pulling beech, maple, or oak to where we park my truck.

 

I run a polaris sportsman 800, and pull a 4 1/2' trailer (1/2 yard or so ... 2000lbs) for clearing rocks from my fields, up and down steep hills and at fairly high (20mph) speeds just fine ... not to mention towing my disk (350lbs) around in the food plot at the back

works just fine for me, and thats with my 300lbs on the seat

 

My head is spinning again. I thought I had it narrowed down to SRA, which really narrows the field, but I'm hearing that it might not be all that important. Back to reading... Thanks for the help and thought fodder.

 

That's a nice little trailer. Who makes it?

 

picture this: lets say you have a IRS atv,you have your trailer hooked up ready to to go haul some fire wood. start loading the wood on the trailer at the rear. As weight is added,it begins to lift your atvs rear end. This is obviously not the correct way to load the trailer especially if your not going to load the whole trailer. Now picture loading it from the front of the trailer,as the weight is added the atv begins to sag in the rear and the front starts to lift. thus leaving you with no weight on the front for traction,not to mention you wont be able to steer and stop easily. The correct way to load a IRS atv is to start in the middle,right over the axle(s),then alternate to the front then to the rear. This way the trailer will stay level and you can see the bike begin to sag. If this happens then you need more weight in the rear. Basically just keep the trailer level and it will be fine.

Now using a SRA atv; put all the weight in the rear of the trailer,same thing as the IRS,it lifts the rear end of the atv.
Put the load in the front of the trailer on a SRA and it wont squat because the weight is on the axle,not the suspension(shocks). Keep in mind your tires are taking some weight so make sure they are aired up correctly or they will flatten out.
This is why SRA would be a better choice for hauling trailers.

This all also depends on your trailer size. If you use a 5ft by 10ft trailer then SRA is better as there is a lot of tongue weight.
If you use a 3ft by 4ft trailer then it really doesnt matter as there isnt much tongue weight.

 

Makes sense... That said, I'll NEVER be pulling trailer that is anywhere near 5x10 where I need to go - trees are too dense. 3x4 is more like it. I will be skidding some light timber though in a pine grove near my house - lots of pine beetle damage in there and I need to do some thinning... WAY less grade in the pine grove, though.

 

on another note. Even if a atv says it can pull(for example) 1500 lbs,doesnt mean you should. Use your best judgement. Need to remember the atv only weighs around 6-700lbs. which is half the weight behind you and could or will push you or pull you down a steep grade. You could actually pull a whole lot more but your brakes may not stop you. anyways,good luck with your atv purchase!

 

Bush Buggy Trailer They are pricy but not as bad as the ATV Wagon trailers.