Have 5, a Svoemesto, Tobeco, and 3 EHPro. All are good. Two of the EH are the new dual air flow, but not black - stainless and gold. The Tobeco is the problem child, although not a "problem." Had some issues with it intially, as the top o-ring was flakey, causing leaks. That taken care of, works fine, but just not quite as well made.
None from the listed vendor, so can't speak to them.
The dual air flow is somewhat deceptive, since the hole under the coil is the same size as in the single airflow models. But it can have a slight effect.
(Nice coil, Wrice. Just one suggestion. Lay the kanthal in on the other side of the screw, so when you tighten the screw it pulls the wire into it instead of trying to push it out from under the screw head. Easier

)