well your right i probably dont need the 70, but im getting this in preperation for a project next year which will probably be utilising twin 12s/15s, and 2 or three small stages, with scooters and camera/strobes, id rather not go and have two different bladders due to cost implciations at the moment, have to get a £600 drysuit as well, so i have the inflation of the suit as well, and i am quite aware of the dangers of a larger wing if the inflater where to stick/free flow, but are there any other major disadvantages to the larger ones? drag? i have quite a wide shoulder span so im not sure if that would be quite an issue but its something to consider
other than that expedition, it will mainly be normal diving activities and wrecks around the UK, the main requirement is for this project as i say, which will be multi stage dives
at what point does the 55# become dangerously ineffective?