Hello,
Firstly, concerning the minoxidil; although if one discontinued regular use of Minoxidil and their hair did fall out, the same thing could be said for any other treatment. So, unfortunately, all these treatments must be kept up indefinitely.
I use Xandrox from Dr. Lee, (minoxidil with Azelaic acid) and I think it's a fairly decent product. It doesn't make my hair greasy. In fact, when it dries, it actually has a stiffening affect that some people call "thickness", but I really just find "stiff". I believe the greasiness in Rogain, and/or generic Minoxidil comes from the propylene glycol, of which Dr. Lee uses less of. I just wanted to inform you of this in case you didn't know, because for me, at least cosmetically, it's nice to not have a greasy head in public (considering I already have the thin hair to worry about!).
Anyhow, on the topic of Revivogen, although I think you mentioned that it worked ok on you, I, myself also used it for a year and although I would say that it did in the end make a some of my individual hairs a bit thicker, it didn't promote more hair. Which is to say, that it didn't stimulate or maintain active follicals.
I specifically asked Dr. Lee what he thought about me rotating Sprio and Revivogen nightly and he responded with this: "The only proven ingredient in Revivogen is Azelaic acid, but if you want to rotate them, then fine." I would, however, add the caveat that his "proven" Azelaic acid has only been tested in vitro.
Here's a link to a web page on his site, which if you haven't read, might be helpful.
http://www.minoxidil.com/Female.htm/female.htm
O.