1. If it doesn't offer a single coil deck, don't buy.
2. If it can't easily let you plug a big (say 3.5/4mm) coil on its deck, don't buy.
3. If it can only hold less than 4ml, don't buy
4. If e-juice seeps from its side or at the bottom, don't buy.
5. If to unscrew its top cap can sometimes unscrew its chamber or base instead, don't buy.
6. If it is not easy to adjust its AFC, don't buy.
7. If it has a JFC but is not easy to adjust it, don't buy.
8. If you can't buy replacement glass for its tank nor its replacement o-ring, don't buy.
If you come across a tank that doesn't have any of the 8 mentioned problems, buy a dozen of them... quickly.
2. If it can't easily let you plug a big (say 3.5/4mm) coil on its deck, don't buy.
3. If it can only hold less than 4ml, don't buy
4. If e-juice seeps from its side or at the bottom, don't buy.
5. If to unscrew its top cap can sometimes unscrew its chamber or base instead, don't buy.
6. If it is not easy to adjust its AFC, don't buy.
7. If it has a JFC but is not easy to adjust it, don't buy.
8. If you can't buy replacement glass for its tank nor its replacement o-ring, don't buy.
If you come across a tank that doesn't have any of the 8 mentioned problems, buy a dozen of them... quickly.