Update: The Photon Sentinel build is now complete! and Im very pleased w the motor's performance. This is the dream setup Ive been waiting for, much lighter than Bafang, much smoother and smarter torque sensing system. The CYC kit fit seamlessly with the proper spacers, cool app to program the controller, mostly easy install on the bike. The custom molicel battery from Matt at BicycleMotorWorks in a fanny pack keeps the weight low and off the bike. Chainline was perfect from first tighten of the shift cable, hit every gear, chainring 1mm off chainstay, how you want it. Major increase in efficiency and dexterity over a bafang system. I used to get 20-25 miles on a 12/15ah battery with efficient use of PAS on a BBSHD. Now with a Photon in low PAS 1-2 in street mode I can still climb everything with ease and get over 20 miles on a full charged 9Ah pack, for much less size and weight - proof that less is better in emtb. Tether battery idea ended up working out very well, I dont really mind a 6lb pack on my belt, allows for instant detach and portable charging. With a carbon frame you want to keep the weight low, especially avoiding heavy motors and batteries which could wreck the frame in a crash. This setup really takes the cake, cant get much better to me, though a wireless groupset like SRAM T Type is the next upgrade. Bike is only 40 lbs w the motor kit. Cheers.