This is only after a quick first inspection and a few hours tinkering.

As a straight battery device it's decent. Adjustments have to be made here and there but I'd give it decent as a straight battery device and no better! These adjustments often end up leaving your accessory/atty mounted on the 510 connection alone not flush mounting making the connection weak and yes this could change with different battery lengths.

As for being a kicked device, well my kick will not fit, no how no way! In one tube its too tight and in the main battery tube my kick is way too loose. I've never seen this before but the inside diameter of the tubing used to make these devices changes diameter drastically!
Try swapping the tubes turning them upside down into the top of the battery cylinder for the kick and this leaves a gap between battery tubes.

I'm left with the idea these are factory seconds or thirds and that they were turned out on automated screws as the two I ordered are identical twins with exactly the same flaws and who knows how many more went through on this flawed program.

No circuit board, full mechanical mod
Random serial number
Laser engraving logo and patterns
Stainless steel construction
Telescopic 510 center pin (silver-plated)
Spring-loaded firing button
Bottom locking ring (is NOT reverse threaded)
Top cap with airflow control ring
Recessed 510 threading connector
Powered by 1*18350/1*18500/1*18650/1*18650+Kick (batteries and kicks sold separately)
BS and loads of it for a meager tidy sum as listed.

So if you like your kicked devices this one is a gamble to a no go. In my opinion it should not be advertised as a kick able device. Even with a sleeve for a kick the changing diameter of the battery tubes makes fitting a kick close to impossible. Good old FastTech QC at work for us!