For adopters , does the latest firmware affect the responsiveness ?
There's no concrete evidence that
any of the firmwares have affected the responsiveness.
Suggestion:If anybody here still has very old firmware it would be good to make some videos of it in operation and compare them with similar videos of the latest firmware (which I could make).
Connect up the test signal, enable one channel, move the trace up and down. Enable two channels, move the trace up/down. Enable four channels, move the trace up/down.
Even then it's quite subjective because a lot of the perceived response depends on how you use the controls. It's much better to 'twiddle' it, ie. make lots of small turns (which I've always done naturally which is maybe why I've never seen the response as a deal breaker).
If you do long continuous turns with no pauses then it's possible to get
no response at all until you release the knob. If you're that sort of person who naturally does that then it probably feels much worse than it is.
I made a blurry video to show this: