How exciting Scarlett! Yes it does have a bit of weight to it, it's a little heavy when folded up, but still manageable
I was going to buy a large sheet of plastic to cover the floor with, correx is a good idea. I think buying two of the storage cubes would be a bit costly just to cover the floor with. Abe tried to get under it but had no success! So it's definitely too heavy for them to lift.
I like the idea of a play pen being bigger than their usual cage so they can stretch their legs a bit more than usual, the size is great.
My hamsters love running around in it and hopping on all of their toys and things.