will this bag WM-versalite +10 shead morning dew and light moisture without getting the down wet

J W, I once had a hard time converting to down too, especially with that question of survival in a wet bag. But when I reflect on all the years I've used a synthetic bag I've found that any reason my bag got wet was from my own fault. If a person wants to keep their bag dry, they'll more than likely be able to do it. And as far as synthetic being fine when its wet is a myth. all the times my synth bag ever got wet, I woke up cold and miserable. If a synth bag will make you wet and miserable and a down bag will make you wet and miserable, then I figured I'd go with the one that weighed the less. This is all from my personal experience, though. Others might have better synth bag experience than me.

The same fabric is used in my Alpinlite 20 degree version. I woke up in the Cirque of the Towers (having fallen asleep to bright starlight) with 3 inches of snow on my bag and 24 degree temps. Not feeling the least bit wet, I rolled over and got another hour of shuteye.

I boosted this directly from WM's site. Also consider that the Pertex shell has some degree of water repellency in and of itself. Hope it helps. Water Management The fear of a wet bag is the most cited reason for people to avoid down. This is a mistake. Any bag that is wet is miserable to sleep in and that is why it's so important to keep your gear dry. You'll find it's a skill easier to learn than map reading. Consider all the avenues available to keep your bag dry, like tents, bivys, and proper camp placement. Then consider the number of times your sleeping bag has gotten wet to the extent that it could not be used. Catastrophic wetting is extremely rare and is an indicator of other problems. You may find that you have indeed mastered the skill of staying dry. All shell fabrics used by Western Mountaineering are treated with a surface Durable Water Repellent finish (DWR) with an 80/20 rating. This is more than sufficient to shrug off dew and condensation. And, DWR's can be easily reapplied as time wears them thin.