I just use the $1 wire brushes from WalMart. They are really easy to clean.
I soak them in Dawn and hot water for 10 minutes in a small plastic container (think Oxyclean). I brush the bristles from 2 brushes against each other to clean the gunk out in-between the bristles. Most of the...
I'm also a home brewer (since 1994) would think they are similar to CO2 tanks. I was told by my CO2 supplier that if you turn them off before disconnecting them then no air gets inside. So, that's what I do.
(Not important, but I did 3 tours at Ft. Bragg). ; ' )
I wouldn't worry about it too much. I have at least 2 clone recipes (from Brew Your Own) and 1 that is supposed to be directly from SN and it is not dry hopped.
Even the recipe I use dry hops it, but since I'm not a hop head I don't. I think it tastes just fine without it.