I have bought a boat load of tanks in the last few weeks. I tried 4 different cheap (under $10) clearos that aren't even worth mentioning. I got a protank 2 on Saturday because it came with my Provari, and I was like...... WHOA! So much better. I was really impressed.
Today my Aspire Nautilus came in the mail, I've been vaping on it for the past hour and it's way better than the protank 2, it's hard to even compare it to anything else I've tried because I didn't even know such a smooth vape was possible. I have a couple of protank 3's in the mail, so it should be interesting how those compare. But as of today I am saving up to buy my weight in Aspire Nautilus tanks.