Got my Delta II and RBA head yesterday, and have spent the day with it, I thought I'd share my thoughts and opinions.
I've tested it with kanthal, and Ni200 in both the RBA deck and in the LVC heads, and tested using both a DNA40 and IPV3 with wattage ranging from 20w to 60w
and temperature ranges from 350° to 450°.
Now right out of the box, heavy, heavy, heavy smell of machine oil, in fact I was beginning wonder after several soap and water scrubbings and vodka baths, boilings and ultrasonic washes if I would ever get the smell and taste out.
With a new LVC head, because the one that came pre-installed still smells like machine oil. I primed it filled the tank. put it together and gave it a try.
Thick cloud decent throat hit, but alas just like every other Atlantis, and the Kanger subtank muted flavor

adjusted air flow from wide open to damn near closed, tried 5watt increments from 20 watts to 60 watts on the IPV3 still muted flavor.
Unpackaged the RBA head
Immediately I as disappointment at the size of the build deck, even though it has way more air flow that a kayfun it is the same exact size as a kayfun, in fact a the lower chimney barrel will screw right onto a kayfun deck. I was hoping for more of a Lemo size deck, but figured what the heck and gave it a try.
Again very thick clouds, decent throat hit, but the same muted flavor, again regardless to air flow, or power applied.
Mind you in neither case did I ever get a dry hit, even while chain vaping at higher wattages and clouds for days but not the flavor I'm accustomed to from my Lemos
I repeated the above on the DNA40 just for argument sake, with my customary twisted 28/30ga build that I put in all my Lemo's on both the RBA deck and in an LVC head, BTW the LVC heads are a snap to build once you get them apart, if you ever built a chimney build this will be easy.
Even with the build and wicking replaced the flavor is still muted.
Now I have tried my best to get to like clearomizers, but never could get a great flavor vape out of any of them and hoped when these sub ohm tanks came out that it would change, but this does not seem to be the case at least with me, yes they are capable of producing thick clouds, but at the expense of flavor.
I'm a flavor guy first and foremost, clouds alone mean nothing to me without warm juicy flavor, so I have come to conclusion that clearomizers, even the ones with RBA attachment heads just isn't for me, and the king of all tanks for flavor RBA or not is still the Lemo.
But if you are one that is not into rebuilding and you are in the market for a good subtank clearomizer I still recommend the Delta II over Atlantis and the Kanger subtank, for build quality and air flow the Delta II wins ..... when you finally get the machine oil out of it.
That being said keep your eye out in the For Sale thread for a very slightly used, de-oiled Delta II with RBA deck in the near future if you are in the market.