Well it's "real" in the sense the nerves are firing, so as real as anything you feel can be.
But as to whether they're firing with good reason, in response to something that's actually happening, no, I think that's the whole problem. They are "over-excitable", and reporting things that aren't there.
I smiled with recognition at the bit about the vibrating phone. I have a come-and-go vibrating patch like this just over my right hip bone and down a bit. In other words, exactly under where my mobile lives in my right trouser pocket. If the phone is on silent I'm forever having to take it out to check whether someone's calling me or it is just the MS nonsense again.
I don’t think somebody else could feel it, no (I haven’t anyone else in the house to ask!)
But I have a feeling someone here once posted that somebody else could. The only way I could explain that would be if the nerve firings were actually causing very minute contractions of the muscle, or of the skin - a bit like a spasm, but on a microscopic scale.
I can sometimes notice fasciculations (“nerve twitches”) in my feet, although these don’t coincide with the buzzing sensations.
Often they are so tiny, I can’t feel them at all - but it looks very weird - as if Alien were about to burst out of my foot!