I used to have that cage. I love wooden shelves. I recommend replacing shelves with wood no matter type of cage you get. Just keep some sand paper on hand and that will easily keep the shelves looking nice. Eventually you will need to replace them but you can take the measurements to home depot or Lowes and they will cut untreated pine for you if you can't do it yourself. (also the company sells replacement shelves but I think its cheaper to go to your local store.
My only complaint about that cage is that the pan is very shallow. I had to put rabbit urine guards around the sides of the cage to keep the pine shavings in. I got my guards from our local farm supply store. You chould also use strips of plexiglass, cardboard (although your chinchilla will keep tearing that up) ect. If you don't wrap something around the bottom few inches of the cage you will have very little shavings in the cage each morning.
I have never used the flying saucer wheel but I think you could fit it in there.