Pros: Simple, easy to use, accurate, does not bend/distort as you are cutting, protective blade covers. Cakes are always level and look fab when layered.
Cons: Nor cheap and takes up space but it's worth it.
I love my Agbay! I bought the double bladed version and use it constantly. Now my cakes are always level.
Quick to set up and quick to use. I used to mess around for ages getting levels/layers right - not now :)