C&C Alternatives Cages built into storage shelf?

I am thinking about trying to foster guinea pigs sometime in the future, and I was trying to find the best setup for multiple piggies that have to be kept separate or in smaller groups. I found a picture online that looked like a pretty cool idea, and I was wondering if anyone here has something similar and if so, how well it works? I hope it is ok to post a link to the picture i found here, because I'm having a hard time describing it... (broken link removed) And to anyone here that rescues/fosters guinea pigs, what do your cage setups look like?