This is one of the most frustrating kitchen products I've ever owned.
Because the thing is, it's excellent at grating. I have an OXO box grater too, and there's just no comparison -- it's much easier and faster to use this one, with less force required from me, because it's so much sharper. Given my choice of graters, I'd use this one every time.
BUT, it's flimsy as heck. It flexes while you use it and develops cracks quickly. The top handles start falling out, the plastic casing around the grating sheets cracks -- pretty much everywhere there's any stress on it, it dies, and quickly.
So if you look at it as a disposable grater, something to use up and replace within six months or so, it's an absolutely excellent 5-star piece. But if you don't think you should have to buy a new grater every six months -- and, honestly, put me in that category -- then it's sort of inexcusable.