Thanks, seems to be a mixed bag.

Grizzley wrote: The motor spins 2 plastic zip ties, "wipers", to sweep the funnel. These are literally zip ties you can buy at any hardware store, $1,99 a pack of 50, and then cut to size to replace. Seems like the whole "zero retention" is based on this component. For a machine designed by an F1 mechanic, seems odd to rely so heavily on this.

I appreciate your first hand review.. Have you tried the 'Weiss Distribution Technique' as I have read that others have done and supposedly there was a small spray bottle offered with the grinder.
Also, the grinder hasn't installed a knocker on the funnel. Have you tried to knock the funnel a few times as I do with my Niche Zero to remove the last tenths loose.

I think you mean "Ross Droplet Technique" - RDT (I get them confused too) - Yes, I have, the spray bottle that came with the Deva is nice, works great, I give the beans a couple mists. It does seem to help, especially with static at the edge of the funnel. I have tried knocking (you can imagine in my frustration... ) but doesn't make any difference.

At mid to high rpm, a significant amount of grinds (4-5g) are "suspended" in the funnel while the grinder spins. When stopped, these 4-5 grams are 'released' from suspension and fall into the cup. I am no scientist, but my guess is there is some pressure differential/slight vacuum created while the grinder spins? This seems like a cool feature (as opposed to bellows, for example) if it works.

I think you mean "Ross Droplet Technique" - RDT (I get them confused too) - Yes, I have, the spray bottle that came with the Deva is nice, works great, I give the beans a couple mists. It does seem to help, especially with static at the edge of the funnel. I have tried knocking (you can imagine in my frustration... ) but doesn't make any difference.

At mid to high rpm, a significant amount of grinds (4-5g) are "suspended" in the funnel while the grinder spins. When stopped, these 4-5 grams are 'released' from suspension and fall into the cup. I am no scientist, but my guess is there is some pressure differential/slight vacuum created while the grinder spins? This seems like a cool feature (as opposed to bellows, for example) if it works.

Thanks Grizzley: the DEVA is a beautiful styled and perfectly sized grinder.
Yet, it might be just this one minor flaw that you mentioned.
Could use a slight modification.

Yes, it checks a LOT of boxes. Overall I am happy with it, and I got a great deal since was original kickstarter. I have never tried that before, so that was a positive experience as well. They do make some bold claims on their website now for the next campaign:

"How do you clean the KOPI Deva?: Since there are no coffee grounds retained in the grind path, there is no need to disassemble the Deva for cleaning. The outside of the burrs can be accessed, without any tools, by removing the dosing funnel. Use the supplied brush to sweep the inside of the funnel and the outside of the burrs as needed."

In my experience, you will need to do this every time you change beans, and then it will take a 2-4 grinds to reach 'zero retention', depending on your bean and your rpm.

I hope more people will share their experience as well.

So is it still the case that the Deva cannot grind for espresso with MP or Unimodal V1 burrs?

Really love this grinder but am concerned about the workflow of having to turn the grinder on and off a few times in order to get the grounds to actually fall out of the thing.

Have others had this experience? Have the folks who have reported this problem figured out any other workarounds (slower RPM's, RDT, adjustment of the "wipers")?

Seems like this grinder could use a knocker or a funnel redesign?

Personally, i really like the grinder not having bellows etc. .
I only need one extra button click to get all grinds out and just do a second one to make sure.
I have 0.0 grams retention with that. As recommended by Kopi Concepts i use RDT. That results in zero static and zero retention.
Couldn't be happier.

In general i agree with Mackerel. I usually do 2-3 extra start/stops at the end. Small price to pay for 'close to zero' retention. I do wonder about strain on the motor, but so far no issues at all with that. Great, consistent grinds, I am happy.

Yeah, I was curious if a couple quick on/off cycles would strain the components. How much retention is there if you DON'T do this? Do some light taps with your hand on the top of the chamber do any good?