My brother is the one that did all the research (including discovering ECF). I had always thought that, if it sounds too good to be true, it probably is. But, my brother was determined and researched it to death.
We started with an eGo-T in February 2011. Then a 510 for more TH. Then 510 cartos. Then the 306. That's where we stopped for a long time. My brother has only recently started experimenting again. But, I became dissatisfied with a couple of bad batches of 306 atties back in the fall of 2011 and started experimenting on my own for the first time.
I tried 808s, 801s, 901s, CE4s, and carto-tanks first. I had bad luck with carto-tanks at first because the first ones I bought came with 3-hole cartos which absolutely do not work well with high PG juice. But, I eventually figured it out, and carto-tanks are the main thing I use now.
I've only recently started building my own coils. Vapocalypse is part of it. But, I'm also sick of poor QC with premade stuff. I'll still use carto-tanks (among other RBAs). I just bought my first Sophia, hopefully the first of many.
A few stick batteries, especially at first (510, 801, and 808). But, mostly eGos. It was probably 2 years before I tried VV. Stil eGo VV though. I did finally get a VV mod, an SID. I hated it. Built cheap.
Now, I have Provaris, REOs, and a Billet Box. I just got sick of cheap trash that I always had to fight. Lots of RBAs, that I'm getting better at building on. The future looks bright.