Depending on where you're getting your Robo from, it might be best to start with a smaller cage than either of those -- younger Robos especially can easily freak out and spend all their time hiding, never coming out to play at all, if they go from a small cage to a giant one!
Personally I prefer the smaller zoozone 1 for Robos
A confident one will use all the space in a zoozone 2, but a scared one will feel more secure in the smaller cage.
Out of the two, though, I would go for the zoozone over the wooden one