I keep mine in a valise in one of the cockpit lockers, it essentially only has safety equipment in it and all that will come out in an emergency. When i bought the liferaft, the salesman recommended the valise in a lockerrather than in a case and exposed to the elements.
BTW: I scrapped the previous liferaft at home. When I pulled the line to inflate it would not trigger the gas canister. We unwrapped it and found the line wrapped around the liferaft and would never have inflated in an emergency.
I changed the service company after that.