It should be ok (not for a baby roborovski though). The good thing about the Hamster Heaven is it is quite a low cage so doesn't have fall risks like some of the other cages, but I'd still fill the base almost to the top with substrate. It would be better to use it just as an empty cage and set it up. ie not use the tubes and penthouse and block the tube holes off, and not use the plastic shelves and houses (the solid shelf might be ok). I'd start with an empty cage and add house and shelf and other items
