My top tip: When you buy a new bag, get some lanolin spray and do all the zippers really well, at least twice over. Do it when you buy the bag or you'll forget.. on a side note who else still hasn't got around to putting their name/number on all boards, kites etc

..Try to spray again once a year if you remember.
I did this on my last bag 18 months ago and it's still going strong, after losing 3 bags to off-season salt crustiness. Believe me I tried everything (soaking in hot water/milk/vinegar, spraying, heavy duty tools) and mangled those bags trying to get the zips to move.
PS Bingles - must be tight with the dog in there too?