I converted my srx into a boondocker last fall. I have a xtc long travel suspension that I put 144" tracks usa extensions onto and mounted it with 2 1/2" drop brackets. I have a 4" riser on it and got the seat reupholstered and raised 4". After I finished this my nose was pretty low and my wieght transfer wasn't the best. I picked up a set of shocks cheap from a 2002 rmk and some viper radius rods. The shocks were 17" long and they bolted right in after I drilled the bushings out a bit to metric size. I was surprised that my stance stayed the same but lifted the front end about 3-4 ". I now have 9 1/2 inches clearance under my bellypan. This really helped my wieght transfer and sure helps when you started ploughing through 2 feet or more snow. And it really helped make shifting the front end around a lot easier. I highly recommend raising your front suspension if you are going with a longer travel rear suspension. I don't know what your conditions are like in your backcountry riding, but here we ride through fields and bushland with anywhere from 1 foot to 3 feet of snow. I find that my 144x2" is plenty for this, the extensions I bought tip up in the back and helps keep the sled to still be fairly manuverable. I don't think you would have this agility if you go as long a skid as you say. I went to the mountains with it twice this year and would have liked more track but if I start getting to addicted to the climbing, I think I'll by a mountain max and throw a 151 in it and keep the srx the way it is. Most of my riding is around home here so I am really happy with my sled for boondocking. So thats my 2 cents, good luck with your decision.