Well, device works fine. I've loaded it up to 12A, 12.60V with a LiPo and it works as advertised.
Nowhere near as precise as my Tenma bench supply though. When charging the LiPo with it, it switched from CC to CV at 12.49V instead of 12.60V. Thankfully it was that way and not the other! Don't think I will trust it for finishing the LiPo charge, but it can charge a 5000mAh at 2C up till it gets to CV mode then I'll use something more trust worthy.
Oh and... the mains switch on the back failed already. My suspicion is they don't use high temp plastic to hold things together and the spring has shifted during soldering. You can push the switch, tap it, thump it, but it will not "click" and go off. So it's stuck on now and I have to pull the plug out of the wall to kill it.
I'm adding a master switch to my TODO list to beable to kill both my power supplies with an easy to reach switch. Currently if magic smoke starts to be released I have to climb under the desk and pull the plug, then come back up and switch the Tenma off too.