Data Masking in SQL

Once upon a time, I thought I would need an entire copy of a table to contain duplicate data in a masked format. Now I’m not so sure. Now I’m wondering if I can accomplish the same thing using a view. Would it be any faster? Slower? Would it save disk space? I think it will save disk space, but I imagine it will be slower. But will the slowness be enough to make a difference? Right now, this is academic. I will have to do testing to see what the real results bring.