Protanks tend to have leak issues due to vacuum loss when the silicone seal over the little chimney above the atomizer fails to seal. You can take a seal of another atomizer, flip it upside down and place it over the little chimney above the original and it will seal it. Occasionally the Iclear I had would lose vacuum and I found taking a silicone cap off another, trimming the bottom and cutting couple slits on side would fix that. It seemed maybe 1 out of 4 atomizers had problem in my Iclear. Iclears were tastier but prone to dry hits. Protanks not as prone to dry hits but not quite the flavor.
Knowing what I know now, I gotta say, forget the clearomizers and go RBA. Even if you cant afford a Kayfun, the clones are better than the clearos. I have a russian clone and although the screws are a little fussy, not one single dry hit since I got it, I love the Mundy Magic wire I wrap with lately, flavor is awesome, cost of ownership so wayyy far down, holds 5ml, never leaks. Leave it in car on hot as hell days and no leaking. The only reason I will by another is to go three post with better hardware. Havent decided just yet but I am starting to see the benefit of an RDA since Im comfortable building all sorts of wicked little
coils now. As far as coil building fear? That was psychological. Its so easy and fun. I probably have 5 dif coils and 2 or 3 of each ready to go. Just gotta use your head, pay attention, and have a little respect.