In reply to Adam Hughes:
When I washed my down bag I used Nikwax Tech wash as I had no Nikwax down wash.
I went into the store to ask as usual assistant didn't know, so I phoned Nik wax very helpful, they said the products are very similar, the down wash was slightly kinder to the down but I could use the Tech wash but just dilute it, Fantastic result.
My bag was definitely warmer and had better loft after treatment.
Some tips are:
1.Its not as complicated as everyone makes out (don't be scared)
2.Getting the bag wetted is the most difficult part- which makes me very sceptical of these claims about down getting wet and not working!
3.Once its wetted be very careful as the down becomes very heavy damage to internal baffles is the biggest risk.
4.Do wash and rinse it thoroughly.
5. You will need a big bath.
6. Don't do it when your wife has just cleaned the bathroom, you wont believe the grim that comes out.
7.Squeeze all water out carefully and handle the bag gently.
8.Fine to spin dry it, gets rid of water, improves drying time reduces risk of baffle damage.
9.Take it down the laundrette and tumble dry.
10. A laundrette is better than your home machine as you can use the big drummed driers gives bag more room to loft.
11. Very important to watch the heat settings as you can melt the nylon bag outer, keep checking it to get temp right.
12. I dutifully bought tennis balls and popped them in to stop down clumping, the lady looked bemused and said if you've tumbled it there isn't any need, she was right.
It is a lot easier to wash down products than folk realise, and the results are worth the effort, I snow holed in Scotland a week later when it was about minus 18 and was snug and warm.