Well, I finally did it. I put together a new 20" TF M-750 frame I bought from an E+ employee when they went out of business and sold off the remaining Wavecrest stock parts with a lightly used X motor and a new 10Ah LiPo battery mounted to the water bottle mount to create a "new" Tidalforce M-750X. I put in the jumper so that I could use a 3rd party battery and love the way the bike feels. Steering is much faster and lighter and the bike feels very lively with a battery that hardly sags at all. I bought the battery from
all-battery.com. It's a high-output 37V 10Ah LiPO capable of putting out 50A continuous and over 80A peak. Unfortunately, they don't stock it normally.
I put it on eBay recently and the bidding ends tomorrow.
(I still have one other 18" M-750 frame so expect another one in the near future)