As above really, looking for an annual policy for myself and one other? Doesn't have to have MTB or other 'extreme' sport friendly?
Post Office
www.snowcard.co.uk - used them for a few years now and had several chances to watch a friend "test" their services. They did well.
My travel insurance is with Flexicover Direct - about £40 for my wife and includes Winter sports. Had to claim twice on the policy over the last 3 years and they have paid up both times with no issues.
Check what some of the banks are offering with their "premium" current accounts, as they'll often through this into the deal.
amex.
Although tempted to switch to the HSBC plus account as well, as it's free with them, as is roadside assistance
Dog Tag
Another vote for the Post Office here.
Atlas cos they will cover my youngest ones medical condition ok so woorth it if complicated
before that used snowcard and i think anyone who has had to claim would say they are good