I've had really good luck using a standard Zefal spring cage and Zefal bottle. The interface is way more secure than anything I've tried with the Podium. Even going through rock gardens with a full magnum bottle there's zero movement. They have a side load version and small bottles, might be worth checking out.
http://www.zefal.com/en/bottle-cages-thermoplastic/67-wiiz.html
http://www.zefal.com/en/14-bottles
http://www.zefal.com/en/bottle-cages-thermoplastic/67-wiiz.html
http://www.zefal.com/en/14-bottles