I tried the vtc6s with 3mm magnets and pretty sure i got a bump in output visually and what felt like way more heat. I wonder if my countersunk magnets contact the carrier better.
The standard batteries arrived at 4.14v so may have been a customer return or degraded. The standard batteries have domed tops which I dont think is ideal for passing 20 amps.
Cool torch so far though.
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F292591534346