Ive been to empty (recover) a plant today with a OE charge of 3500 kg.
It aint a huge plant just getting on a bit 1986.
2800kg out so far (ran out of storage) with a surge drum still 1/3rd full + 1/2 full intercooler (hi side float) . I think about another 2000 kg will come out before its empty possibly more. It really supports the gas and go brigade