More about Silencer

CAME TV follow focus

http://www.came-tv.com/cametv-wireless-follow-focus-controller-motor-inside-receiver-p-660.html

I have an RTMotion. It's phenomenal. Three axis controller / receiver, aux included in the base model. Short of a $30k Preston, it's the best deal if you'll ever have more than one axis and not a bad deal for a single axis (just about the same price as a BFD). The reason I went with it over Bartech was the size and weight of the on-camera motor and receiver. The RTMotion is TINY and very very powerful.

DJI wireless follow focus. Remote can be used with the X5 without the motor also.

http://www.dji.com/product/focus

Opteka FFR-900 Motorized Remote Follow Focus & Zoom Controller with Shoulder Support Rig for $249

http://www.amazon.com/Opteka-FFR-900-Motorized-Controller-Camcorders/dp/B00AQNRXDS

@alvaro for $100-150 it'd be worth it. $300 is a little steep, perhaps. It is a good idea and looks well thought out, except: it's probably not silent, has a ;limited range of 2 settings" 110 degrees and 160 degrees. You would have to set one side to your inf focus and then let that range become as far to near focus as it will travel. Also, if the range of travel is farther than the lens has, it will probably grind and push the motor away/off the lens. Also you'd like to have a reverse direction switch for the times you are using Nikkors or have to mount the motor flipped around another way.

You could probably build the same thing from servo city for less. I did once see a youtube video if a guy who had done something with 2 motors for his anamorphoic set up to maintain focus, with parts from Servo City and it was a lot more high tech than this.

I would love to see somebody come up with an affordable hardwired solution, or this company to bring out a v2 with these suggestions. I don't have the skills myself.

Thank you @Cfreak , as you perfectly said, 100-150€ would be fair enough in my opinion...but I´m still thinking on pulling the trigger, as I think it´s a good solution to control focus by myself when I´m working in videoclips without any AC , and maybe it can also be used by an AC close to the gimbal as the cable looks like longer enough to do that.

I contacted the seller to ask if it could be returned in case of not being satisfied with the quality of the product, and he answered me with an offer of 290$, which makes me think that he does not accept returns...

As for the noise, I sent him a link to Tom Antos's review of the Wondland wireless ff and he replied that the noise it´s similar. I told him that ideally he would send me a video made by himself to check the actual noise of his product, but he did not want to, claiming that the noise can be altered in the edition (in reference to the Tom Antos video) to make it quieter or louder. But this answer, added to the non-response about the return policy makes me think that I should not buy the product ...

Finally I have purchased the Keyeasyfocus. The seller told me that I can return it if I´m not satisfied with its quality, so I think that if it works right I will be happy even though I know it is expensive...I am very bad with DIY things, and I like very much the simplicity of this electric follow focus, so for me could be a good gadget.

I am still thinking on purchasing a cheap wireless unit like the one that @bannedindv has shown before, or other models even cheaper like this one: http://www.ebay.es/itm/132026840591?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT ...but I wondering how can I mount them on the Ronin-M if I want to operate focus by myself...any ideas? Thank you.

Issue with all cheap electric FF is bad noisy motors and sometimes even bad fixing.

CAME TV is around cheapest you can get with reasonable quality.