My Brompton Swytch kit came about 10 days ago, 4 months from ordering, and I finally got around to fitting it today. How anyone can do it in 30 minutes beats me, I took 3 hours including changing the tyre over and figuring out which of a selection of parts to use, where exactly to position everything, and generally taking my time. I suppose I could do one in 30 minutes now, bar the tyre change.
It worked properly first time, so at least I got it right. Darkness falling, I gave it a 5 minute test. As expected, with only a crank sensor and no torque sensing it's much cruder than my Bosch-powered Cube. Once the pedals are turning, it applies the selected level of power which is a little disconcerting when it continues to accelerate even after reducing pedal effort, but I know I'll get used to that.
What is weird is that the wheel has only radial spokes, 28 of them. I asked my engineer daughter how she would go about calculating the forces when rotational force is transferred from hub to rim. The answer I received was "no idea". It feels solid but how long will it last? The instructions advise regular checking of spoke tightness.
Edit - I've now given it a run, 7-8 miles including a short steep hill, and I'm getting used to it easily. I used power level 2/5 which helped me up the steep stretch in bottom gear which is fine for me. I still find the constant power a little odd, and frankly when I want to bimble I end up going too fast, which I then have to regulate with periods of not pedalling so as to cut the motor power. I'll experiment with varying the power level instead. Battery level has dropped by one blob.
Overall I am happy with it so far.