I have the Zenco Flow, and bought extra cups, so it's also the Duo. Got the "wood" base. The Flow bubbler uses water, the Duo cups don't. Bought a set of Sommelier, and while they are beautiful, the more open top is more likely to let vapor out. It looks like they now have new glass called The Fusion that uses water. Other Glass options are available, and you can get different colored bases.
This vape is so much fun! It can do flower, but I've never bothered, and just use for concentrates. When I'm gifted 510 cartridges, I'll use them with this, but it's mostly used for rosin. It's easy to load, easy to clean, and the vapor is strong, but soft and light in the lungs. It's sort of like Long Island Iced Tea. You sip and think "how pleasant" , then try to stand up and realize you've been walloped.
It's nice for sipping or chugging, and the flavor is good. I use the lowest setting for cartridges, then pulse rather than hold, and the next step up for rosin.
It looks like this sort of vape is coming up, and Pulsar has the Sipper.
I bounce between the Dab-Ready and the Zenco, and try to rotate in other concentrate vapes. If I want something fast, like now, I grab the Zenco. If I want a more chill session, Zenco, and if I don't want to clean a banger, Zenco.