You're right, the protank looks great on the ProVari. On the eGo... a bit mismatched, but the cone adapter does give it a sleeker look.
I take it you're a bottom coil fan. I recently got an EVOD and while it's not bad I'm still on the fence a little bit. I've been using my T2 more lately. When it's working well I get better vapor out if it than the EVOD. And, I guess I'm liking the warmer vape too. Although the T2 has its gurgling issues.
What voltage are you using with the 1.8 ohm coils? I find with the T2 I'm good at around 3.6v (eGo Twist) with LR heads (2.0 ohm I think).
I was T2/CC carto before moving to the Tabac BCC. I think there's a quality difference between the Tabac vs. the T3 but their virtually the same. The one thing I liked about the Tabac vs. the T2 were the silicone rings. The 'inside' one in the T2 can get out of place rather easily - but once you know that you can keep it in place on refill and they worked well. I preferred the no dry hits of the tabac bcc vs. the T2 - mainly because of the bottom coil. However, I haven't had as good a luck with the evods. Gurgling and juice in the mouth with the evod vs. none with the tabac bcc's. I've tried some of the fixes on the evods and they were better, but I also don't like the metal skin or the mouthpiece on the evod and the lower volume so I'm pretty much 'all tabac bcc'.
I got the mini protank just to see how they were and may use them on two flavors that can tend to crack plastics - mentholyptus and absinthe. I've cracked some T2's with both and one T3 with the mentholyptus which is 'medicine cabinet strong'

IF I find better flavor on my other flavors, I may switch over to the mini's but I've tried some of my flavors on the regular protank and only a few 'benefit' from the glass over the plastic. I have no consideration on 'outgassing'... I was a 3 pack a day smoker
I'm using eGo-c upgrade batts and using them in the 'constant mode' 3.3-3.4Volts for the 1.8ohm coils. One flavor can take the 'variable mode' which is just a regular 3.7v cycle, which is warmer. The lighter flavors ylang ylang and lotus flower, I use the 2.2ohm coil. The 2.4/2.5/2.6 ohm coil is way too light for my lightest flavors and unfortunately, some vendors sell the clearos with those 'oem'. For my espresso mix I use an eGo Twist set at 4.4-4.5v with the 1.8ohm tabac bcc.