BmwTek
The indications are that you will lose freon and will continue to do so and more frequently as time goes on with the recharge.
The reason is not the freon because they don't go bad from the inside out but rather the outside in. They were manufactured and not coated properly and in time they get eaten by microscopic mites...read on the net!
The replacement ones are dipped in plastic on the ends and are available new or from an aftermarket supplier. There is such a demand that other suppliers made them, not just Behr. Dlr price is around $1k while others are from $200-700. Dealer inst rate is about $1200 as it takes just 21.8hrs to do the job. Been there, done that!! Ugggghh!

TobiasMB
300SE, 300CE, 190/5.0