Thats my fiances worry too, the chewing/eating factor - but they sell fabric ones in the pet store and hes been more known to try to drag fabric (blankets, towels) left near his cage into it to curl up in. And rats are actually very smart so I doubt he'll decide that it is lunch.
Spoiled? I must spoil my 2 rats rotten then! They usually have a hammock or two. Mine DO chew them a bit on the edges though. Yours looks a lot better made then mine though, so I doubt it'll be a problem. Very cute rattie though.
I don't mean to nag...but even aspen isn't great for rats. Especially one with a respiratory infection. The aspen can actually cause respiratory infections. I'd recommend Carefresh. And quarentining Jimmy while he's sick is VERY important.