In reply to Gary Coggon:
I've got a PHD Minim 400 and have found it is superb. I used it in the Fish River Canyon where night time (desert) temps dropped to between 0 and +5 degrees and was never cold. I use it now for everything except winter camping.
It is very light and packs up very small. The best bag I've ever owned and well worth the price tag.
If you ring PHD they will make it to order with choice of no zip, half zip or full zip and will ask what side you want the zip.
I don't know about the Alps - it may not be warm enough for camping high, but ideal for the Cuillin Ridge in Summer where I have also used mine.