I don't know what coils you use in the protank 2 but if you use the
regular old protank coils (which Kanger now calls "MT32" coils but fasttech has not updated their package pictures) then they have silica wicks and taste nasty.
I frequently vape EVOD clearomizers (they take the same coils as your protank 2) and I use the Kanger SOCC coils (not SSOCC), which are the same as the MT32 coils but they have cotton wicks instead. They taste so much better than the silica wick version and I have never had a dud.
Here's a
fasttech link to the ones I'm talking about. I really think you should try them. They come in 1.5, 1. and 2.2 ohms.
As far as the "atomizer short", this is the one complaint I have about these coils. The problem is that a few years ago kanger switched to using soft silicone rubber for the positive pin insulator instead of the harder white rubber they used to use and if you screw the tank on too tight on some mods it squishes the insulator too much and causes a short. A solution to this is to remove the positive pin on the coils, place
one of these TINY little orings on it then put the pin back in. In other words there will be an oring between the positive pin and the silicon insulator.
It could also be a fatigued insulator on your mod's 510 pin squishing too much and causing a short.
As far as the coils only lasting a couple days, well, that is usually a problem with high sweetness and color (the darker the color of the juice and the sweeter it is, the harder it is on a coils). I only vape a moderately sweet peppermint juice and my factory coils (all of them, not just the protank coils) last me at least 3 weeks.
Lastly, a lot of today's "MTL tanks" won't have anywhere near as tight a draw as your Protank 2 in case that is important to you. So just be forewarned.