I do think that glycerin is a major component of the commercial needle lubricants. It's an ingrediant of many different kinds of paints so it won't react badly with any of them (there are probably exceptions to this). I know it's in gouche, a good amount of the acrylics availble, and doesn't react with enamels, laquer based paints or even 2 part urethain based paint.
The consistency of the stuff and the resulting glide is perfect. I just dip the tip of the needle in the stuff and then insert it. The stuff is fairly viscous and will get where it needs to go. Neither glycerin or commercial lubricants are expensive, so the cost per use of either is really really low. I say use whichever is easier to get or stick with the commercial stuff as it is designed for this kind of work.