The two big things in the comparison, IMO, would be:
1) The centralized steering of pro will feel much different than the high-angle over-the-motor steering of the IQR... In technical mountain riding...for me, the PRO wins out. Not to say that I have not seen people rip on their IQR's in the trees.. It just seemed that they were using more effort. I'm helping a local guy this season build an IQR up and we are trying to figure out how to integrate a more vertical steering post configuration like in the pro or M-Cat into the sled... It should go in there pretty easily.
2) the amount of bodywork that is in the snow is less on the PRO than the IQR... The "cab' on the PRO is narrower and requires less rider effort than the IQR... That being said, I've been on IQR's with wide fronts that held tenaciously to a sidehill, but the tradeoff was in tight quarters maneuverability because of that width.
The IQR is considerably more rider fwd than the PRO...I found myself standing far back in some situations on the IQR that I would ride the PRO "neutral" in.
The IQR that I rode was a well setup unit with a carbed 800 small block, Z-broz 43 wide front with spindles & grippers, Trail tank, Challenger Extreme 155 x 2.5" paddle, Mtn Tamer rear and some other goodies...
I've seen plenty of mountain conversions on the IQR.... but 90% of them were not very well done and just seemed "thrown together" to me... that would make a huge difference when making the comparison. It takes some serious cash to make a well done IQR-Mtn conversion IMO.
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