I test-rode a K-100RS back in the day. I also found it too buzzy for my taste and continued on riding a series of R-models. Last year I came on a low-miles K100RS at a price I thought too good to pass up. I jumped on it. I've since become very pleased with the bike. There must be a good deal of variation in the vibration level from K-bike to K-bike, as I know I've not become tougher in the years since that test-ride. Today I don't have any problem with my hands going numb when I ride my K100RS. As for heat management, no one can say that is not an issue, but even in the hot, arid environment in which I often ride I can manage it just fine by keeping my knees somewhat splayed out in the airstream. Those old K-bike are way undervalued in the US market and can be great economical sport-touring companions.