I used Procyon for YEARS. I fought idiots on the boards over this product from day one, until they just stopped shipping east of the Mississippi. No grandfathering in established customers, no thank you ... nothing. Then, I found it really hard to deal with the one distributor they had for eastern states. He wouldn't ship powder, only liquid. So I just stopped using it.
I have mentioned this problem several times over the years since and have seen countless others complain and have never seen John mention that he sells it until now. Good to know.
I did notice it would do a number on the brass fittings. You ever notice how it builds up on you hydroforce? I wouldn't use it as a rinse because of that. I don't know if it still does, but back when I was using it for all those years, you really had to be careful not to allow your prespray to come into contact with wooden furniture. It would leave a white powder residue that was a killer to clean off after it dried.
Since moving on and finding other options, I doubt I will go back, but it's good to know Olsin sells it if I ever decide to.