Looking at the reviews and the pictures I am sorry to say but the cage sounds like and looks like it is made for smaller animals such as rats and ferrets and maybe guinea pigs. People with rabbits said that it did not support their rabbits weight.
Why would a NIC setup be too big for your room? You could just make it a small one like one by two, or two by two, or one by three grids. That wouldn’t be too big. Also NIC is cheaper and I think they are better just because you make it, so you control how stable it is and the design to fit your room. Also remember that you do not have to make it a rectangle, you could make it a L shape or whatever shape fits your room best. You could make it a L shape and put it in the corner of your room. I have my rabbits living in my room and The NIC cage doesn’t take up that much space. It is the pen that has taken over my room, but I don’t mind.
Oh and thank you RabbitPam – I was too lazy to paste both the things 