I loved my BO-6's so much that I regretted parting with 5/10 of them... so I ordered 10 more. Direct from the same source (just google it). It would appear that the BO-6s with half chamber/half tank are version 2's... they're definitely not imitation. The smaller chambers of the version 1 flooded so easily and now there's a bit of room for excess liquid to sit. Also, when putting them back together, it was tough to fit the wicks in and they frayed quickly.
Another improvement on the version 2 is that the drip-tip socket is now funnel-shaped to draw condensation back down towards the wick. The old one's were flat and had often had to be dried-out with some tissue... or risk sucking it into your mouth. Ew.
Unchanged is the draw holes on the side of the 510 connection. They're are still too small. I'm not looking forward to widening them...
By the way, ask nicely and they can switch your drip tips from the stock chrome/steel. I got black xylonite vase tips.
I also ordered their silicone bottom-coil tanks (replaceable atomizer not RBA), but that's another story...
On the subject of tubes, you can't just use a small DC tank tube because the BO-6's tube is longer... unless you can get them custom-cut at the source... but lol, plastic is plastic. If anyone manages to get pyrex tubes that fit, please tell us. If I get bored and interested, I might just invest in a pyrex glass cutter... but tracking down tubes of the right diameter might be more trouble than it's worth... these things aren't exactly easy to take apart and stretching the plastic tubing seems to be part of the package deal...
I'm guessing we bottom-coil folks are in the minority... I've seen the BO-8s everywhere and a million top-coils RBA and replaceable... Oh well.