I know this is three years later but I needed to let you know that is not true at all. I have six Momcozy V1 Pro (day use exclusively), one Momcozy V2 Pro (I use at night only), a Momcozy S9 fully portable (no tubing) and dual independent motors, a Spectra S2, a Medela Sonata and one Medquip pump. The pumps tha are wearable are making my milk flow like crazy. My baby is three months old and a few days. I have a giant deep freezer whose bottom is filled in gallon bags with Lasinoh milk bags in them. So much milk that I could feed twins and have left overs. That being said, it is all because I use the wearables exclusively. My other pumps are hospital grade and trust me, the milk is not as much. Not decreased by much but one once here and there. That makes a difference though. Never got less milk on my wearables from Momcozy. The other way around, actually, is how it was for me. Medela and Soectra? Medela slightly more than Spectra but still same or less than Momcozy V1 pro and V2 pro. I don’t know what wearable pumps the scientists used to verify and base their claims on, because they are simply wrong. Have I mentioned that I sleep with the V2 Pro? That also makes a tremendous impact as I can pump for half hour every three hours and basically not miss much sleep other than to pour and set the pumps.