Today I drove for the first time with my M8 + Spektrum in a RDX. Equipped with a MMS3 (same as KO VFS-1), KO PDS2143, GP3300's and a Corally Black Series 12x1.
No glitches at all, response time is also very fast. So I'm very happy with my Spektrum. Only my laptimes have to go faster a couple 0.1s faster for the race tomorrow.
But I don't know if there are problems with newer KO servos.