I've been taking these 1mcg B12 tablets for over 2 years now.
A couple of years ago I was diagnosed with Miller Fisher Syndrome, which is a neurological disease where your immune system attacks your nerve fibres following a simply infection or bout of flu.
It was pretty serious stuff. I couldn't walk and was in hospital for 2 weeks. I couldn't see properly for 6 months!
I did a fair bit of research and discovered B12 is part of the "repair crew" for nerve coverings. So I asked my Neurologist if B12 would help. He said it wouldn't do any harm. So I started these tablets, 1 per day.
I do get nerve "flare ups" with burning sensations etc, but since starting the tablets, they only last a day or so!
Can I scientifically prove anything? No, of course not. But, I am convinced these help and will keep taking them for the rest of my life.