Over the long term, excluding DOAs, I had four eminent failures, all four caused from tank dumps into the micro-USB port of Yihi mods.
The USB port on the Yihi devices is permanently powered - as long as the battery is inside the mod. So, any liquid left inside it keeps corroding the contacts and the circuit tracks.
Sad thing, the mods still work, just their port is not functional, both for charging and for loading profiles.
The clue is in the Yihi warranty, one year for the device, and three months on the USB port. Instead of being cheeky, shouldn't they fix their design?
I Checked the internals (ML class and Q mini), and a couple of tiny copper tracks below the USB connector have been 'erased' - so to speak.
I ended up in... no longer buying Yihi.
Pods... A Smok Fit, an Aspire Breeze 2, and Aspire Nautilus AIO died in the last three months.
The Smok Fit had a failed circuit, which stopped working at once, without an apparent cause for the failure.
The Breeze 2 had the pod retainer clips broken; which seems to be a manufacture error, it seems they used the wrong type of plastic for the job.
The AIO failed after the full pod e-liquid content was dumped into the inner circuit - following two short, back-to-back airplane travels.
Vape on,