For PSF, I prefer Redline, Amsoil, RoyalPurple, or Sweet. I find that regular PSF's can be a little annoying during the winter. GM even sells a cold climate PSF.
Gunk, Wynns, BG, Valvoline, Lubegard, Prestone.. should also have generic PSF's that'll work just as well.
Siphon/refill is quick and easy. Buy a couple bottles and siphon/refill once a week until you run out of new PSF.