I applied last month for the maximum 200K. Costs me £24 pcm for 20 years, but it's only a life insurance, not personal accident like PAX. It was very easy though - all I did was fill in the form - doesn't even ask about your specialisation - and less than a week later I received all the documentation in the post. Job done!
I don't know about multiple policies, but I somehow doubt it, otherwise they might as well just let you have a bigger policy in the first place.