spaceman, I just happen to be vaping the Cerotank, an Aspire Vivi Nova, and a Mini Naughty right now.
The Cerotank is really everything that Werkz indicated. I've described it to others as "everything the Kanger Aerotank wanted to be, or should have been". It's quite a bit smaller than the Aerotank mega, but quite similar in design. It's elegant and sleek, "masculine" even. It doesn't have the feminine qualities that I so love in my Mini Naughties, but it's got a lovely elegance to it. Yes, it's quite a bit bigger, but not obnoxiously big at all, and I do like small tanks.
The fill is a breeze and much easier than the Naughties. There is a bar across the top just under the top of the chimney, so you can actually tell when to stop filling.
It's sturdy. It smacks of quality.
The airflow controls are easy to use and quite effective.
I must say tho, that I don't mind the lack of airflow adjustment on the Vivi Nova. It is airy enuf for me, but that's obviously an individual choice.
As far as why more people don't have them or aren't talking about them? That was MY question as well. It appears they've been marketed primarily to Europe. If you do a search for them you'll see that many European vendors carry them, but none here in the US..... yet. Other than one seller (great seller) on eBay.
I imagine that the popularity on these WILL grow in time. Seems some of us just got in on the ground floor.
I'm using one of mine on a Provi Ti at 4.2v with NiteLiteVapor vliquid which is 65/35 PG/VG. The other is rocking on an iStick, but I'm too lazy to go in the other room to give you the wattage on that.