Anyway you look at it, no matter what kind of shape you are in, they are heavy:D
PST E8 130s weigh roughly 44.5lbs, empty, with a standard valve. Double that, you are at 89lbs.
PST E7 120s weigh roughly 39.5lbs, empty, with a standard valve. Double that, you are at 79lbs
PST E7 100s...