I do find the flavour seems enhanced with ni80 but I believe I’m nickel sensitive so I can’t use it. (‘causes me huge, painful mouth ulcers)
I’m having to be much more careful particularly with stock coils as a lot of them don’t state the material used and even when they do I have to think twice.... I had a tank that used ss904 and I thought I’d be fine, a week later I felt like I’d been using Ni80. Turns out ss904 has a high nickel content (22~28%).
I can't say I've noticed a taste difference that I would describe as metallic.