In Nebelwerfer 2 the Frankensteined Gimson GR02's 24/1 with HK 2838 2850 KV inrunners mated to the Trackstar 25A sensorless speedo's work fine. And that's with large, soft 130mm RC wheels. And that one is standing by for months now. On the other hand, that's a 6 kg raptor.

And yes, it's the starting speed that is a problem with the current Calliope drives. Once it goes, it goes well.