I also have this cage
It is very sturdy - mine has a small dent from when I managed to walk into a wall whilst carrying it but the bars aren't flimsy and don't bend easily. The platforms aren't great but can be used, neither of them really allow for toys to be placed on top as the pink one is sloped and the green is more a track than a platform. Despite this the cage is a nice size and is pretty escape proof. For a dwarf you should have nothing to worry about - the front door is very secure and the top door will probably be out of reach and I haven't had any problems with it with my Syrian. Overall I would recommend it as it is sturdy and although the platforms aren't great they are easily removed and can be replaced with better ones if you want. I have a labyrinth house in mine that doubles up as a platform so that could be a good option as the penthouse is very hard to clean so I don't use it.