Speaking as a Mil CSRO (Combat Survival Rescue Officer) and a qualified Military Pilot and CPL holder I noted the comment about the IM suit being an overkill. Well I'm afraid I dont agree. 22 miles in flight is nothing..I agree, but try swimming it, after ditching, in bad weather, with possible injuries, a swell and not to mention the water tempreture!! The only time you will need an Im suit is when you NEED an Im suit...if you know what I mean. An overkill maybe but not if you need it. It will increase you survival factor by 300%. With the water temp averaging around 11 deg in the Channel you will be lucky to last 25 mins and thats in a good condition (physicaly) add all the previous factors and hey, I dont think we would reach you in time.
We wear ours on EVERY trip across any strech of water that is more than Autorotative distance from solid ground, and we have two engines, flot gear and an aircraft that will stay afloat almost indefinatley if put down correctley (and a bloke in the back to get the dinghy pack ready!!)
They are not uncomfy to wear and the peace of mind for you and your loved ones will far outweigh any expendeture. And it means we wont have to fish your body out of the brine. We allways like to see a smile when we get there, it means your alive.