Counter top RO system after long disuse?

[greenpassion]

I was just reading an older post where someone was discussing RO water, flushing, etc. In this post, he mentioned that he was concerned about using his RO system infrequently, and one of the responses was from Ray. He mentioned that the only problem with an RO system that hasn't been used in a while is that if left with no water in it, the membrane will dry out, and damage it. Well guess what. I have one of these counter top systems, and used to use it very frequently as I used to grow in SH. But that was over 3 years ago...and I recently got it out of the cabinet and began using it A LOT as I have 3 humidifiers going, and use RO water in them. After each use I empty all the water I can out it, and had done this when I'd put it away so long ago...My question is how do I know if it's still in working or if the membrane is dried up?