This turns a basic Igo w4 into an outstanding RBA. The airflow options alone make this worth getting -- there are two large slots which can be adjusted by turning the top cap.
Other benefits are the reduced chamber, which makes a noticeable difference in flavor. The top cap also lifts off so you can drip right where you want to. Much easier than even the widest bore drip tip.
The build quality is very good with tight, but not too tight O-rings. Nice machining overall.
It comes in a little drawstring pouch. That's nice, but I would have rather they skipped the pouch and included some spare o-rings (none come with this).
Pair this with an igo w4 and you'll have an RDA that performs as well or better than ones costing 3 times as much.