I have had a number of different electric fillet knives, Rapala, Mister Twister, Bubba, ect. and my all time favorite is an old American Angler bought at Walmart, that I've had for over 20 years. I force myself to use the Bubba now because I paid so much for it.....and it's cordless, but I actually like the old battle-axe American Angler the best.
Battery chargers? I go through them like toilet paper. Sealed onboard chargers are the WORST. Schumacher vented portable chargers last longer than anything else I've had.