Right, I fitted the Kunteng sensor (actually it has no branding so I hope that's correct) very easily today. It fits into the Shimano pattern BB cup's splines very neatly. It may need a dab of glue to hold it in place, but I'll keep an eye on that. It's a much less conspicuous bit of kit than the standard two-part sensor.
After fitting, I called EBC who very helpfully talked me through the display/controller tweaking settings. Once that was done, seeing as the sun was shining, I went out for a test run on a road/off-road route. The sensor works perfectly and the motor kicks in significantly quicker than on my Woosh. I can accelerate away swiftly now, which was something I could never do on the Woosh.
On assist level 5 it gave the same boost as full throttle, only I could keep my hands on the bar ends. That was something I missed using the throttle alone. On setting 2 or 3 it was ideal for the muddy off-road sections of the ride. Nothing too technical, just a muddy bridlepath and a puddle-strewn canal towpath.
I now have a bike I am 100% satisfied with and I heartily recommend EBC and their kits based on my experience up to now.