My wife and I love our Kanger AeroTanks. We don't use the stock coils though - I rebuild them with 29 gauge kanthal, and wick with KGD cotton, 1.4 ohms. These things are not cloud machines by any stretch of the imagination, but I do think they give a satisfying and tasty vape.
I like how they can be refilled/topped off without completely disassembling. Likewise with popping in a new coil.
When it's time to clean, they come apart nicely.
In over a year of using AeroTanks (original v1), I've had a couple of bases separate into pieces on me. In the base alone, there are seven individual parts: Bottom with 510 threads, two springs, ring, top (threaded to connect to tank), pin, and insulator. All of these pieces are pressure-fitted together. Screwing the base too tightly on to a fixed-pin mod will eventually cause them fall apart. You can press the pieces back together, but they'll separate again.
I haven't had a v2 base separate on me yet, but I suspect these are also pressure-fitted.
The v1 base is only $3.53 from FT (
https://www.fasttech.com/p/1654500), so it's not a huge maintenance expense. The other metal parts of the AeroTank are very solid. Of course the glass can break, so you should have spares for when it does.
I've only had the SubTank for a couple of weeks. I can say I don't care for the stock coils. I've been using the RBA part, and I'm pretty happy with that. I made a couple of attempts at rebuilding the stock coils, and I have a way to go before they compare to the RBA part. I'm sure I'll get it to work.