In reply to Ian Campbell:
There is a world of difference between sleeping in a bothy in October, and sleeping in a tent high up on the plateau in winter!
If you plan to do both, then I suggest a cheapo Tesco sleeping bag will do you for the bothy trip this autumn. This can then be your doss bag, that you don't mind getting a bit of abuse. Or get one of these
http://www.rockrun.com/productlist.asp?CatID=559&BCat=448,509,559&r...
If you do want to go to the Cairngorms in winter, then I suggest a good warm bag.
http://www.alpkit.com/sleeping-bags/ have a good selection. Which one to get? It depends on how warm or cold you sleep. I have a pal whose sleeping bag is half the weight of mine, and we are both comfy. He doesn't have a more sophisticated bag with better insulation: he just sleeps warm, and I sleep cold.
Don't underestimate the Cairngorms in winter. It can be a wild, wonderful, overwhelming place.
