I can vouch for the tanks from Valley View Vapes... I have about 8 Triple V tanks in rotation at all times, polypro and pyrex, grommet, cap, tank screw in the side or needing a needle to refill. I carry two 3ml polypro tanks with me at work, one with high nic and one without, and I stealth vape when I am able. At home I rotate about 3-5 polypro tanks since I do a lot of DIY, while the pyrex tanks with the nice drip tips are for bringing out and showing off to smokers... I buy Boge cartomizers from VVV, punch them, rebuild the tanks about every 3-8 weeks depending on the juice, and don't have many problems. I've had leakers every once in awhile, a rogue carto that can't handle a citrus juice I made, but EVERYTHING ends up leaking that juice. Heavy cinnamons, citrus, oils, dark coffees, caramels, and mints have not discolored/damaged a single tank from Triple V, but I have a bag of other tanks/clearos that are etched & cracked from heavy juices.