If I didn’t already have an awesome cage for my degus I think one of my top options would be a Ferret/Critter Nation Cage. I used to live with someone who had 4 ferrets and he purchased one of these ferret nation cages for them and they really are wonderful cages. You’d need to do some custom work to make sure there’s a way to keep bedding in the bottom without access to the plastic the degus could chew through.
Ferret Nation Cages on Amazon.com
The prices on amazon are really good too. It’s a lot lower than list prices at private stores and the shipping isn’t too bad either.
The quality of the Ferret Nation and Critter Nation is good. They’re wonderful cages and while it definitely takes two people to build them – once they’re built they’re very sturdy and reliable.
I especially like that the Ferret Nation cages are expandable – I dunno about you but if I had it my way my degus would have a whole room to play in!