He's talking about the V3 Stardust. I don't recommend them if you want to be frugal. Even though they come apart now and can be rebuilt they crack A LOT. You drop it (and you will) it cracks. You put it in your pocket for a minute, it cracks. Top, or bottom, it will crack. They say they don't crack and I'm sure people will try to argue with me about it but they crack. That's why they sell replacement tanks for it. Why sell replacement tanks for something that never cracks unless... you guessed it... it cracks.
On top of that, if you vape them for too long of a burn the center post cooks your juice and ruins it (as evidenced by the much darker juice that always remains at the bottom of your tank no matter how much you top it off), and the coils are very sensitive and over time they will come together and create what is known as "hot spots" which gives you "dry hits" and basically spells doom for the system. On top of all that, they leak if you turn them at anything more than a 90 degree angle. If you overfill them, they can also leak into your battery's juice well when you have a crack building back pressure pushing it down (which is inevitable).
INSTEAD, I recommend the Vision Vivi Nova, the big sister of the Stardust. It holds more than twice as much juice, and although it costs 3 times as much (about 14-15 bucks for the tank system) it comes with 3 atomizer heads (the important part) so it's like getting 3 stardusts anyway. They are easier to take apart and clean because they are bigger, easier to fill, and also quite rebuildable. Another feature that they have that the Stardust does not is the option to buy (for a few bucks) a metal tank for it - which makes it invincible to cracking or damage, and also serves as a standoff weapon (danged hobos, you never know when they'll strike!). SO, that's MY recommendation. If you would like to learn more about them please refer to the following channel:
Vaping Estarra - YouTube and do a channel search for the Stardust and the Vivi Nova and make the comparison yourself if you wish. He also shows you how to rebuild both models of clearomizer. The only things that the Stardust beats the Vivi Nova on is compact size, and looks, but only one of those is functional (hint: compact size).