First, a very fine SB'er has sent me a PDF of the VH book (3rd edition). Now I have some reading to do.
Meanwhile...
@tbone1004 Yes, I am moving to Charlotte. But, I think it will probably be easier for me to get air fills at a scuba shop than put that much effort into my relationship with my local VFD.
@kensuf My thought was to get some twinsets filled with air and then use a booster to do the air top-ups with a twinset for the source gas. Of course, in that case, maybe I would get the twinsets filled with EAN32 and just stick to Standard Gases for my dil. I normally keep my dil bottles all filled with 18/45 anyway.
@KWS I deduce that your home fill unit is something I know nothing about and that it must produce argon as a byproduct? Got a link to the kind of unit you're talking about? Regardless, I do want to be able to produce trimix for deeper diving.
A further thought I have had is (please correct me if I'm wrong) that I will need a booster, no matter what. I want to be able to fill my O2 cylinders to 3500psi (as I do now, when filling at my LDS). It occurred to me that it is probably not a good idea to attempt to do that using a Continuous Mix compressor setup. I suspect that scuba compressors are probably not safe to feed pure O2 into the intake side. So, I would need a booster to do that, regardless of what else I do.
I am curious about the (other) limitations of a continuous mix compressor setup. Like, can you easily produce TX10/70 from one? What about even more hypoxic mixes? I will get started reading the Vance Harlow book and see what I can learn from that.
Thank you all for the info so far!