I'm looking at upgrading my sleeping bag, and have to admit that I've never really used a down bag (aside from an OLD army surplus bag when I was in Scouts and din't really know what I was sleeping in). I pack a Slumberjack 30 degree synthetic presently.

My main concern is in regards to condensation. Understanding that the quality of bag and (presumably) amount of fill plays a role, about how much condensation can a down bag take before it starts to lose insulating ability? I spend most of my time hiking in an area famous for its morning dew, and would rather not freeze my butt off in the shoulder seasons (I'm not really a winter kind of guy anyway). Anybody have some knowledge to drop concerning this, or with some specs that would suit me well, before I let some salesperson talk me into a ridiculously expensive bag that I might not really need? Any thoughts appreciated.

Ben