The problem is that not all plastics crack so readily. People like transparent tanks, but transparent plastics are not the best for chemical resistance.
The worst plastics for chemical resistance are acrylic (Plexiglas) and styrene. They are relatively cheap, easy to extrude into tubes, and very clear. A distant second is polycarbonate (Lexan); it is a very tough plastic, clear and far more expensive. Sadly, it does not have great chemical resistance, but will generally survive in mild environments.
Pets (Coke Bottles) are very good as far as chemical resistance is concerned. Polypropylene has outstanding chemical resistance, but it is transparent and not clear. If your juice cracks those, it will generally be too late to make your last will and testament.
Heat plays a big role in chemical resistance; the hotter the environment, the poorer the chemical resistance. Some devices dissipate heat well before the heat gets to the plastic tube, others do not. The sub ohm vaper really should stick to glass. Some do like it hot!
Now that I have totally confused you, you are confronted with the fact that very few devices tell you about the material in your tanks.
Check the threads for your particular vaporizer.
While it is a safe route to take by following the guidelines, they may not apply to your devices. My fruity juices demolish CE 2's and 4's, yet I have not had any problems with any of the other replaceable top and bottom coil clearos.
