It's a nice steady speed - not too fast and not too slow!
There's no twiddling involved - just press a button on the remote to focus closer and another button to focus further.
On the 523Pro, there's even a press to Auto Focus, release the button and it's back on manual.
It has a good zoom rocker which is either proportional or with preset zoom speeds - and there is an on/off button for the camera as well.
I've set the camera up now with the various peaking and zebra functions on the control wheel, so I can cycle between whichever is apposite for the function; the focus is set to manual so that the remote can control it; the exposure is set to manual as well and is controlled by the joystick.
However... there is some audio interference when using an external mic - although the internal mic is perfectly clean.

So is there anything the ZR has that the Manfrotto simply doesn't? The difference in price (for 521Proi) is about $100-150US... (only about $40 for 523Pro). I'm keen to get one, but not two :)

Compatible Zoom Controllers
 

Is anyone else using a non-Canon zoom controller successfully with the RA-V1? I'm trying out the HF S11 with the RA-V1 to try to replace a set of ancient GL1s for multicam shoots. We have a set of cheap SignVideo Zoom Commander II controllers that worked great with the GL1s, and I thought since the RA-V1 uses a LANC connector that they would be compatible. But only the power on/off and auto/manual focus toggle switch work through the RA-V1. I can't zoom, adjust manual focus, or stop/start record.

Anyone know if the Manfrotto 521Pro or another lower-cost zoom controller works with the RA-V1? I see that Robin uses the 523Pro, which is at least cheaper than the ZR-2000, but I was hoping for something that costs much less. I don't need good ergonomics, but I do need zoom, focus toggle, and record stop/start to work. Any suggestions?

Do I understand well that in order to be able to use a remote (such as ZR-1000) on a HF S20 or S21, you'll need the RA-V1? You cannot just plug in the remote in a LANC terminal? If so, where does that attach to the camera? Hopefully not on the shoe.

I believe you can plug in LANC without an adapter on the S21. For the older models like the S11, you need the RA-V1, and it does plug into the shoe.

Thanks for your respons. Can anybody confirm this?