I've got a pair of Slumberjack sleeping bags that have been fine for the car camping my wife and I do.  We are going on a 6 day canoe trip later this month.  Our bags are good for the temp range on the trip.  However, they are bulky.  If we use the stuff sacks we have for the bags, it will take up a goodly amount of space in our gear dry bag.  I'm thinking a compression stuff sack will help with this problem but am unsure of what size to get.  Any suggestions?