I picked up a power steering machine for my father a few yrs ago - 2009 Polaris Sportsman 550 EPS. The steering is spooky good. Makes me think something is broken when I get back on my atv after riding his. Most of the trails on our hunting lease are pretty rough and primitive (nothing like that pretty trail in the pic above), the power steering machine is much easier and less tiring. Tried it out on the road at up to 55 mph, was smooth and straight, no wobbles or vibration. The polaris power steering is automatically variable so reduces assist as speed increases. Definitely worth the $.
