Dry/compression bag size

I have a Western Mountaineering Megalite (overfilled W/ 1 oz. 800 fill down). I use a lightweight Outdoor Products dry bag of about two liters in size. It's large enough to let me roll the top over three times but still not require me to compress the bag until it's rock hard.

I don't think you need a combo dry bag/compression bag. A regular lightweight dry bag will do very well.

I have a Marmot Helium EQ, size long (a bit more bulky than a regular length Helium bag). It fits perfectly in each of the following compression bags:

Sea to Summit sil compression bag–size small
REI sil compression bag–size small
Sea to Summit eVent compression bag–size small

I this case all of the small bags are appxoximately the same volume. Of the three, only the S-to-S eVent bag is completely waterproof.

I hope this helps.

I have a Helium membrain which I easily stuff into a 20 l sack along with sleeping clothes. If I'm not trying to put anything else in the sack, the bag will fit into a 15 l sack, but, to me, it is not as pleasant to do so. I find the 20 l sack allows me to push the sack down to the bottom of my pack (wrapped in an overlying trash compactor bag as well), keep my clothes dry, and allow other things to mold around the bag. In my opinion, the stuff sack that comes with the bag, which the REI site says is 8.8 l is too small for easy stuffing. It also makes a rock which does not as easily accomodate other items in the pack. At a very minimum, I'd suggest a 10 l bag if you want to be able to easily close the dry bag well enough to keep out water.
Jim

Gents,

Thanks for the replies! It looks like a small (or equivelant amt of liters) will work fine for me then.

I know there are plenty of threads on "to compress / not compress", so I won't take the thread there. I just need the ability to fit alot into my pack. Most of my hiking/backpacking is a means to get me to a rock climbing opportunity, so I have to pack accordingly for the extra gear required. I use the UL techniques I find here though to make the rest of my adventure as comfortable as possible.

Regards,

Mike