I have been using the Better Vessel as part of the Early Adopters Program for about 6 weeks now. I wanted to become familiar with it over a period of time before writing a review. Up front, I would state that it does an excellent job of removing the crema from an espresso. I use fresh roasted coffee, grind my beans immediately before brewing, and use an NIche Zero grinder and a Profitec Pro 500 espresso machine. I get lots of crema, and my espressos look great. The Better Vessel removes virtually all of the crema, with a resultant lessening of bitterness, and allowing the underlying flavors of the coffee to come through more notably.
So why just 4/5 stars? That rating has to do with the fit and finish of the device, and a few other minor issues. First of all, it will only hold about 38 g. of espresso comfortably. I think one could get to 40 if filled right to the top. So, I think the capacity needs to be increased. I think I did read that and increased capacity is in the final version. Secondly, a couple of the nibs on the "adapter ring" that actuates the valve mechanism were broken off in my device. This does not affect the function, but just makes assembly more fussy. Again, a problem that is easily solved in the final version. Perhaps my biggest complaint, and this is still relatively minor, is that if one is using an espresso cup with a handle, then getting the valve to actuate involves some fiddling around, as the handle prevents the device from sitting squarely and level on the cup. Easily solved by using a cup without a handle, but I think there should be a way to engineer this piece to accommodate most espresso cups, handle or not.
I fully expect the final production model that will ship in a few months will address all of the issues that I have raised. I also would anticipate a higher level of fit and finish than this 3D printed version. Should the final version meet those expectations, then I will gladly increase my rating to 5 stars. I really do like the concept, as well as the results.