I have used
www.costout.co.uk in the past who do annual multi-trip worldwide superplus cover for a family of 2 adults and up to 5 children for £75. This includes 17 days of winter sports cover.
The only problem with recommending insurers is that most of us have never had to make a claim and do not really know how good the insurer is when a claim is necessary.
Costout has been featured as a Which best buy for several years.