For what it's worth I've used a "Cocoon" silk liner for years and it's still fine. Not sure where to get them but I'd replace it with a Jagbag now anyway since they're lighter and cheaper. You can get them in the UK (someone on ebay) but getting them direct is cheaper.
I've never hand washed it, in fact I'm not sure I've ever hand washed anything in my life (except when away travelling!).
It just gets slung in the machine on a "Silk" setting along with all the other silk things like: silk liner gloves, silk thermals and silk undies.
I've found silk stuff works really well; light, durable, warm (even when damp) - and silk thermals don't get smelly like synthetics.
Since I'm on about this -
http://www.nznature.co.nz/ is a great place for everything except mummy sleeping bag liners. Delivery is surprisingly fast a few days at most.
Edited: 12/04/2007 at 13:57