If you want to turn right, you squeeze the trigger on the right and the wheel on that side stops/slows while the left wheel continues to turn, allowing you to maneuver easily.
I have no way to compare the difference between power steering vs non power steering, as I've never used a snowblower before - period. I've just grown weary of shoveling 80' of driveway over the last 16 years and figured I'd get something to make my life easier as well as make a few bucks if I can.
It seems to work well. It turns around on a dime using the power steering levers. Obviously, I've not used it in snow yet, so I can't comment on how well it will work in that environment.
I saw the other model you mentioned, and with the sale price that I got this one for, I decided that I'd spend the little extra for the added convenience. Not sure if I mentioned it or not, but it was on sale and then I got an additional 10% off bringing the price to $666.00.