Yes, I mean after the ESC setup.
I did contact Mtroniks.
First reply - very fast - was that my Tx was set up wrongly. But apart from changing to Mode2 it was at factory defaults.
Second reply - equally fast - was that I needed to reverse the throttle direction. Which I did and it just made the motor stop at the other end of stick-travel instead. No (useful) change there.
Since then, not a bean heard from them. Maybe they're thinking about it.
I have since found that if I reduce the throttle throw on the Tx (by adjusting the throttle curve so it only goes from 20% minimum to 80% maximum), then the ESCs work as I expect them to. But why should I have to do that? The servo's work fine with full-throw output. Why not the ESC?
Both units were from their "ex-demo" sale range, which claims to be items which have been randomly taken off the production line to test quality. In which case they've already been tested by Mtroniks so it's unlikely they're faulty. Anyway, two units with the same fault...?
Reckon I'll send them back for refund. They don't seem to be able to cope with full-deflection Tx output.
They are also a nightmare to set up on a R6M Rx, because you have only 2 secs after power-on to enter the ESC's setup mode. But the Rx won't have locked to the Tx by then. So when you enter ESC setup, the Rx is sending fail-safe min-throttle to the ESC, which confuses the setup as it expects the stick to be at neutral. The only way round it is to power the Rx by a separate battery temporarily during setup. Which means disconnecting the ESC's red lead during setup and reconnecting it afterwards. An all-round pain.
So what should I get instead?