Hello99 – I was personally by Rav Elyashiv, yes years ago when I was bochur, and I know many others as well at that time. He paskined based on the outcome, if the shaver did too fine a job it was considered haschasa, and assur according to the shita that the outcome is what is important and not whether the instrument is similar to scissors.
The maaseh with the Chazon Ish I have heard from other sources, but I heard this when a bochur was asking Rav SZ Auerbach the shaila, and I was standing right there. The point here again is whether the outcome haschasa is important or the means, i.e, scissors are important.
I believe the Machon Hatenhnologi Lehalacha has a long diyun on this topic.
To the best of my knowledge, Rav Yaakov Yisroel Fisher was matir as well. If my father in law was still alive I could verify this. Maybe my wife or brother in law, or one of his sons knows.