I finally am able to report back here that I have my Coppervape SkyLine and have run about 7 tank fulls thru it. With the glass tank that came with it I have no leaks, drips and very little condensate collecting anywhere. I changed out the o-ring for the JFC straight away. Am running mine with the smallest Air Disk out of the 8-pack extra that I bought from FT, 1.06Ω 6 wrap 2.5mm coil, 28g NiCr and 9 watts in power mode with KGD as wicking. I too notice a somewhat muted flavor, but very similar to my Lemo V1's flavor, so not bad at all, just not as Clear and Sharply defined a flavor as my DF Siren or CV Hussar. Juice flow back or darkening, YES, but I have no problem with that, as many others have already stated previously, It's an Non-Issue with me.
The only problems I have had was when I put the bubble tank on it, it leaked straight away. I took the Cleito Bubble tank off and measured the inside circumference to find that the Cleito tank was out of round by more than 10 thousands (.010) or 2.5mm, the bubble tank was just cut oblong instead of round, on both tube ends and would not seal properly enough to even get a good vacuum going, and refilling it was a disaster. I have a second Cleito tank I have not tried yet but will in the future.
I'm in the habit with most of my RTA's that have a JFC of closing the air flow, tipping the whole tank upside down then closing the JFC control, Filling the tank, tipping the tank upside upside down and when the small air bubble raises to the top (bottom) opening the JFC then the air flow control, tipping the tank right side up and screwing the tank back onto my mod. I get no gurgling or flooding at all, but that is just my habit of filling RTA's that have a JFC especially.
I really like my SkyLine and use it daily, along with my Siren, Hussar, and Toyota.