I use carbon/fibreglass composite cylinders on my Kiss. The fibreglass layer is outer most to protect the carbon underneath.
The liner is aluminium. The aluminium neck of the cylinder is prone to corrosion....I don't think it's a particularly marine friendly grade, and needs
protecting with a layer of epoxy resin.
There is some discolouration of the epoxy of the cylinder, and I have made covers to protect them from knocks.
As for value for money, well in some backwater pacific countries even a 3 litre aluminium cylinder is like US$ 200 and I got the composites at a better price than that so it made sense to me,....for travel they're great.
