I know they're useful for organisation but I have so few things in my pack I'm not sure if I really need them, especially for my sleeping bag. Can I just fling it in the bottom of my pack or am I liable to damage it?

I just use one 25l (ithink) Sea To Summit waterproof drysac to contain all my gear save the tent and sleep pad. I don't bother with a sleeping bag stuffsac. Sea To Summit stuff sacs are lighter than Exped equivalent. I use a small 5l Sea To Summit sac for accessories - gloves, hat, 1st aid etc on the outside pocket. The 25l sac makes a good pillow when stuffed with any spare items and sealed with some air inside.

You don't really need a stuff sac for a sleeping bag but in this climate of ours you'll certainly need a large waterproof bag inside your pack. One of the advantages of not stuffing your sleeping bag into a stuff sac is that it can expand and fill up your pack, which, in the case of many ultralight packs that don't have any kind of framework, helps to make it carry a bit more comfortably.

cheers for the answers- I've been backpacking for a while now so i'm used to our weather:( The stuff sacks are something i've always had without questioning it because originally they were good for organising my gear and I thought protecting my stuff- theres been quite a bit of stuff i've ditched that was only there because 'that was the way you're supposed to do things'.

yeah. Same for me.

When I am using a waterproof sack, I am not using the compression stuck sack given with the bag.
However, in the summer time, when it's not really likely that it will rain, I don't use the waterproof sack.... In this case, I use the stuff sack (which is lighter). Because I don't like to think that my sleeping bag is directly in touch with the bottom of the pack (moisture, sharp rock).

Depending on the configuration of your pack, stuff sacks can be practical for a few items (food, shelter, electronics/papers)... Maybe, try first to use the various pockets of your pack in the optimal way. If you feel that you need stuff sack to organize all of that, then use it.... but if you're wondering whether or not you should use them, it's probably that you don't need them!!! :P

Rather than trying to find good reasons for taking a new item in my pack, I try to find how I could manage without it/them... =/

Keep it simple! [thumbup]

Then, with experience, I know whether or not I am ready and willing to carry the extra weight...

I don't think I'd ever not put my sleeping bag in a waterproof stuffsack in the UK, however good the weather looked -- I reckon the weight saving is not worth it given the chance I'll be unlucky and have a miserable night. I usually put any spare/sleep clothing in too. And I carry the smallest Exped drybag to keep my car keys and cash in.

I find a couple of them useful. I would always carry food/pots in a seperate stuff sack to protect my gear from spills and soot deposits. My rucksack (GG vapour trail) has no hood pocket or internal pockets so my valuables, passport, glasses and electronics go into an exped xs drybag hung onto a clip inside my sack. I always know where they are and they are easily accessible. A second XS drybag accomodates my first aid and wash kit. I use a fully waterproof bivvy, so my down sleeping bag stays in it an no further protection is necessary. Like cameron I use my bag to fill up space in my rucksack. It only gets compressed as much as required to accomodate the rest of my gear. In general, all stuffsacks supplied with down clothing sleeping bags etc go straight into the bin. I don't see the point in them. On the whole the benefit I get out of organising my gear in this way is worth the extra weight of a couple of stuffsacks/drybags. Silny stuffsacks are pretty light in any case.

I usually use one stuff sack for my sleeping bag, one for spare clothes, one for food and a mesh bag for my cook kit. I also used to use a sea to summit sil liner. Each of the stuff sacks weigh 25g and the s2s liner weighs 74g. If I get rid of the 2 sacks for the bag and clothes that saves me 50g. I'm using a murmer pack which is spinnaker and should therefore be waterproog except the seams plus I'm taking a gatewood cape which will provide total coverage for the pack unlike a pack cover- that's a saving of 125g pretty much- my down gilet only weighs 150g!

I have a love hate relationship with them. I love the fact that they keep stuff dry and organised but hate the additional weight.

I now use Sea 2 Summit bags as these are 1/3 weight lighter than Exped.

I've never got on with the idea of a sleeping bag filling the bottom of a rucksack in a rucksack liner because despite the fact that it fills the corners it takes up much more space in my experience.

I use dry bags for sleeping bag, spare clothes and a small one for camera/mobile. Everything else doesnt really need a dry bag or stuff sack. I might pack food in a carrier bag which will be used to dispose of rubbish.

Depending on the shelter I'm using I mostly leave the stuff that itcame in at home.

I used to use a plastic rubble sack as a pack liner. I now use a sil-nylon pack liner from Integral Designs that is lighter.
I also carry my sleeping quilt loosely in a sil-nylon stuff sack at the bottom of the pack liner. A couple of supermarket plastic bags hold my food, cooking gear etc. outside the pack liner.