From the movement I can say is - all very round and smooth. the rails have to every now and then lubricate with the enclosed gel somewhat, then the rolling resistance is lower - but enough for me now after a month with each one drop per side.
Schrittänge and rotation are very natural, no strain on the knee, very quiet, clean movement.
After the two Kettler, which I had previously and a New Horizon I must say, this device is so far along with the Kettler Mondeo (which I also highly recommend) the best I had so far - especially a lot of performance for the currently very greatly reduced price.