I change megazorb once per week, and spot clean the bits under their hidey dens and their hay tray daily ... tbh if I was going away for 10 days I wouldnt feel bad telling the piggie sitter not to clean them out fully just to scoop out the worst bits, the stuff still smells fresh after 7 days apart from their potty corners, hay tray and under their hidey dens. I like the smell of the stuff tbh! Its quite earthy and much nicer than stinky piggie fleece.
I have a 16sq ft cage which is the same as 3.5 x 3.5 or double the size of a ferplast 120 and one bag lasts three clean outs and I'm pretty generous with bedding
the only thing about megazorb is that it is so light that it seems to get all over the house!
I am going to give finacard a go as the bag is 220 litres I think for less than double the price of megazorb but well see :-)