My 1997 Jeep Grand Cherokee Limited came with the Goodyear LS tires that look much more like passenger car tire than SUV tires, but I am happy to report that for the 3 years and 36,000 miles that I had the vehicle, the tires rode as smooth as glass at any speed up to and including 90 MPH. (yeah, I drive fast, but safely) I rotated the tires every 5K miles and never had an alignment done. There was good tread on the SUV when I turned it in to the dealer at the end of the lease. One note which may or may not be relevant to all of your experiences is TIRE INFLATION. I am very anal about this subject and follow the instructions of the car guidelines very carefully and sometimes I overinflate a tad to compensate for my aggressive driving. Maybe if some of you kept your tires at too low a pressure, it caused the tires to go out of round when sitting overnite or perhaps with too low pressure, the belts may have shifted. I agree that Michelins have good quality control and seem very consistent in their overall performance and tread life. Another good tire company to consider is Dunlop, which makes a wide assortment of tires for all types of vehicles. Bridgestone makes some great high performance tires and the best snow tire in the business....Blizzak. Yokohama tires are also a good brand at very reasonable prices. Sorry to hear of your aggravation with the shimmy. I have had this on some cars and it is quite annoying. Regards, Andy Simon in NJ