I just did the 30 day satisfaction guarantee - and returned my Rail 9.9.
I don't think there was anything particularly bad about it... I just wanted less assistance and to use my legs more - so I have bought a Levo SL instead.
A great bike, and great fun to ride. I just felt that it was giving me too much help on EMTB mode. Well put together and solid feeling. Bosch motor is torquey and powerful - and not too noisy when pedalling. Battery integration into the frame works really well, and is simple to remove.
Negatives:
- Several chips on the bike before I'd even got the Invisiframe on - straight from the box. Had I not returned it, the shop were going to replace the whole bike for me! The TREK logo stickers were rough and badly cut on the non battery side.
- Even the range topping 9.9 weighs over 22kg when the pedals are on. A lot of weight to lift on the bike rack, or to try and bunny hop. Trek weigh and supply the bike tubeless... so you can't automatically take 400g off the advertised weight for removing tubes!
- LOTS of pedal strikes for me. The same route on the Levo SL had barely any. I was considering shortening the cranks 10mm.
- The KIOX display was mounted in one of the best places I've seen it - however was still awkward and unsightly. For me, Spesh have this sorted with a few LED's on the top tube.
- Bosch motor is really clattery when coming down fast root / rocky sections when not pedalling.
- Difficult to maintain 16+mph on flat ground due to weight / motor drag, and riding without assistance is VERY hard work.
- Clutching at straws... but the bottle cage mount position mean you'll struggle to fit a full size bottle without it rubbing the frame.