I've got a plastic version, but if I need to shred a block it hurts my hands after a while, because of how light it is.

I bought one of these to solve that problem (this also has a finer cylinder for a thinner grate):

If I ever need more than a pound, I can probably use the disc on my food processor, although the last time I tried, I didn't freeze my cheese prior, and ended up with a lot of smeared cheese on the disc 😬