http://trade.ferplast.com/fercatal/dep/57921499.jpg
This is the Duna Fun cage. I'm sorry but I haven't had time to transfer my own yet.
The Ferplast Duna normally sells for between £25-£40. It is half a wire cage and half a tank ie. it has bars but a tank top and it is suitable for all the Dwarf species. The bars are so thin that not even a robo could get through them. I would however say that it is not suitable for more than two Dwarfs. It is not in my opinion suitable for Syrians as the tubes might cause some difficulty, as a larger ham may get stuck in the tunnels.
Pros
Easy to clean apart from tubes.
Lost of room for a single or pair of Dwarf hamsters.
Bars are thin so no chance of an escape unless you leave the top open.
Good ventilation.
Can expand the tunnels to make a rotosatak system if you want while still having one main big cage area which is a good size
Cons
Poor access ~ only door is in the roof.
Lots of hiding space for an untamed hamster.
Limited space for larger wheel making it definitely unsuitable for a Syrian.
Limited toy placement space.
If your hamster uses the tunnel as a toilet urine can exit the tunnel as there are holes on the top and bottom.
Unsuitable for a large Syrian.
You can cut the cage down in size as the tank top can clip to the base, so you can tame you hamster and then add the rest of the cage, solving the hiding space issue when your hamster isn't yet tame.
You could also wrap the outside of the tunnel with some paper stopping urine escaping, but this may provide limitted ventilation.
Overall quite a good cage which you can solve its faults with a bit of imagination and effort and still give your hamster plenty of space and a good home.