The storage tubs we use are for going under a bed. I suspect that since the apartments are small in HK, people sell a product like this so you can store clothes and things under a bed.
The hide is OK, but if it were lower it would be better. If they have been living 12 years in the cage how you show it above I am thinking they are no longer afraid of being a little exposed and that will be just fine.
Good luck!