Honestly, I was totally on team pre-shredded for years! The time saved felt huge. But then I actually timed myself grating a block last week and it was like five minutes, tops. The texture is so much better in a baked dish, and that price difference really adds up over time. I get the convenience factor, but once you try it, it's hard to go back.
Wait, but what about the cleanup? Grating a block means washing the grater, and that thing is a pain. That's the real time sink for me, not the grating itself.