Jags, I've found Outdoor Research [OR] products to be really good for backpacking, cycling, canoeing, etc. Which one to buy depends a bit on the intended use, and the exposure to rough wear & spiky/poky things. I've used weights, as follows:
1) ultra-light silicone-treated nylon, with a drawstring, is a good general-purpose stuff sack to go inside a backpack. There are different sizes. These are splash-resistant, but since they're closed with a drawstring, aren't waterproof. They don't like to be dragged, scraped, poked with spiky things either. I store my sleeping bag (down) in one of these, because it goes in turn in my backpack or canoeing drybag, etc., which are themselves dry.
2) still very light, but a wee bit heavier, is the one with a roll-top and fastex snap fastener. These are really handy, and being a bit sturdier, can be used on the outside of a pack, or on the top of a bike's rear rack, etc. With the rolltop sealed, they're waterproof.
3) there's a grade up in weight & durability, also with a rolltop & fastex snap. I use these on my motorcycle's rear rack. I have one which is 15 litres, and two which are 45. They're excellent--also waterproof when the top is rolled.
These last two compress by rolling down the top (you have to squeeze the air out first) and then snapping the fastex buckle closed.
OR products are very well made, and good value. No hesitation about recommending them, if they suit your purposes. For backpacking, cycling, or motorcycle camping, that's what I'd recommend -- so long as one is careful, and treat them well, they'll treat your contents well in return.
If you want heavier, and heavier-duty bags that you can drag across gravel at portages, kick along the bottom of your canoe to re-trim the weight, throw them at bears, etc., then suggest you look at Sealine products. They're very tough PVC, and durable. Their kayaking bags also have a one-way valve to purge air.
For compression using belt-style straps, I'd just use separate straps & wrap them around the bag.
Mountain Equipment Co-op (our local co-op) has its own line of similar bags. I've used them, and they're sturdy & good value. They're slightly lighter than the Sealine bags, but in my use (cycling, kayaking and canoeing) I haven't found them to be in any way fragile.
For prices, you could have a look at the MEC website:
www.mec.ca MEC sells all three lines.
Hope this is helpful,
J.
