I just spent about 3 hours trying all sorts of builds. Even that single coil in between the posts (vaped worse than a cig-alike). I was thinking maybe I just can't do a TC build for this particular atty, so I decided to do a Kanthal build. It's been a fun experiment, but I'm not 100% sold on TC anyway, so no biggie. I made a dual 26G spaced, 2.5mm...went crazy, for some reason, and did 10 wraps. It came out high for a dual coil...1.2 Ohms...and it jumped every time I hit it....anywhere from 0.8-1.5! As you can see, I'm new to dual-coils. However, it was vaping ok so I figured I might be on to something. So I ripped it out and redid it using only 6-7 wraps (I forget), and it came out to a stable 0.45. It's vaping great at 35-50W.
When I did that final build, I noticed my V-deck wasn't tightened all the way so I tightened it. However, that made it so I could not see the coils through the airholes. So I loosened it a bit...is this what you meant? I thought you were talking about the base (and not the deck). Maybe that's what was wrong with my TC builds (tight deck). So I intend to try them again, but atm, this Kanthal build is working flawlessly.
Also, I went back to horizontal, but I made sure I cleared the spot directly below each coil so the air flows above and below the coils. I think this is important since in my previous horizontal, that spot was packed with cotton and it's probably one of the reasons it vaped horribly.
I still wish I could set it just a teeny-tad more restricted, but I can probably get used to it. So, atm, the jury is still out if it's my favorite. However, it's definitely a contender, and it wouldn't surprise me if it does become my favorite the more I use it.
Finally, I have been trying to chain hit it (as much as someone with Asthma can), and never even came close to a dry hit.