Yup. I think the stated limit is 15 pounds each (give or take). I don't know what a 12-pack bottles weighs, but I've had one in each side case and been just fine.Used my panniers yesterday loaded to 25-30 lbs each. Think that exceeds the load limit(?)
Got up to 90 mph (oops, thanks Ivan for making this thing a rocketship) and bags stayed on without issue...