My Opus BT-C3100 smells like magic smoke and looks like this. I suppose I could change these resistors and it might be OK, but I could also buy things.

I’m looking for 2-4 slots; it should fit protected 21700s; it shouldn’t have a noisy fan that runs all the time like the Opus; USB-C input is preferred, but not required.

I’m broadly aware of what’s on the market, but I want to know if you love or hate yours.