I have turbo levo comp -21, I have done 2000km hard trail/bikepark riding with it. Perfect engine, wouldn't change it to anything else. Normally using only trail mode because Turbo is so addictive that after that everything else feels lame But of course when I want to have fun uphill, it's Turbo time! I have also daily commuter with Bosch Gen 4, after a year and 4000km's the engine failed. A software error and I got new engine after 4 weeks.