The Infineon is the bike controller I got for bike.3 and bike.4. In bike.3, it works well, but because it's sensorless, it's not so good at acceleration from stationary. I think that would be a problem with any controller - the answer is, don't use sensorless motors.
In bike.4, it performs like a dream. It feels like flying.
So I bought two more controllers, a 6 fet 3077 and a 12 fet 3077. My plan is to put the 6 fet into bike.4, which will free up the 12fet one there now. And then I'll test it, because the 6 fet is only rated at 25 amps, and although I've been told that it should be good up to 60, I want it to be able to run at 40 amps, and I want to test to see that it really will.
The next bike I plan to mod will be bike.2. That's the Haro folder. It works fine, but when I replace the controller, it'll work even better! That should be a pretty easy mod.
Then when that's complete, I intend to tackle the Forza, which will, when finished, become bike.5, The Forza was my first e-bike. It's quite heavy, and doesn't fold. But because it's so solid, it'll be good for trips to places where I can be sure I won't need to do any lifting. I tried to sell it on Ebay a couple of months ago, but I only got offered £150 for it, and it's worth a lot more than that as spare parts. I mean, the motor wheel alone is worth £150.
It uses 36 volts, but I plan to run it at 48 volts nominal (meaning 57.6 volts when fully charged). I need to strip out the old controller and associated parts, and put in the new one, which will probably be a 12 fet so that I can run 40 amps. I can use my existing batteries, chargers, etc, so the only cost to this conversion will be the controller ($92) and a throttle/switch ($16).
As well as the controllers, I bought three throttle/switch assemblies, and three torque arms.