Well that XR1 looks like a beast....Looks like all the good roots blowers are all nylon stripped. While it looks like the screw blowers are not.....I like the idea of no maintenance to the rotors just for consistency...When I was down at Jan Cen years ago, I got to watch Mike Jr re-strip a couple of rotors and make the nylon end caps.....All hand made tools and bench....WAPITA that looked like. couple that with 18 strips to an XR1 blower, and that seems expensive. I am also learning, none of these are cheap blowers....Just wondering if there is something better than a Procharger...Roots just look way better.