It's been roughly 6 months since I got the Phantom x which I use daily as a short commuter ebike to go to work (very short 1 mile round trip). For a sturdy, reliable albeit slow, (17-20 mph) production bike, I am happy with it, and it uses safe LifePo4 but that won't stop me from modding it the day the warranty runs out. (the warranty actually did me some good because I had to give it to the dealer for battery repair.) Reason # 1: all the weight is on or over the back tire (motor, controller, and battery) making the steering a little squirrelly. Reason # 2: It's a hardtail and all that weight on the back magnifies the bumps. Reason #3 After building a 72v50a bike it seems a little slow.
I'll probably use a safer chemistry than lipo and hang the battery box in front of me. The physical size of the battery won't matter because if you look at a Phantom X there is no triangle to restrict battery box size so I can get a 60v15Ah headway setup if I want. The motor is DD and sensored so I'll probably go lyen 12 mosfet controller that will also go in front. Those changes will address all concerns I have with the bike. Only 18 months to go on the warranty.
Project bike-Genesis v2100, Crystalyte HS 3540 with 72v40A controller and four 5s8Ah zippy lipos in series.