Last week I bought two (always need a back up) pro tank 2s to use on my Zmax. Straight out of the box one worked fine (*edit..I originally said it worked great but now I know better) but the second one had issues. The draw on it was so tight it was like trying to drink an extra thick milk shake with a swizzle stick. Barely even usable. I took it apart, fiddled with it, loosened it up, tightened it up
nothing. So I went ahead and ordered an aerotank base for it. Vapemail finally arrived today (less than a week but so anticipated) and...Ahhhh. Success. So much better. Nice airy draw and tons of vapor. All is well in the world today.