Are you referring to the big pot of quickshade where you dip your model, or the dropper bottle washes? I use the latter all the time, spread with a brush; the former tends to leave a too glossy and patchy result for my tastes. It's a nice, natural brown that can be used to quickly shade (ooh!) many colours, and if you're going for a quick and easy "one shade for them all" method, Strong Tone is among the best options there is. I painted my entire Conan King Pledge very quickly using AP's Strong Tone wash as a cheat for shading. For a more "artistic" result I tend to mix purples and dark turquoises into my shadows, but that's for painting contest stuff rather than board game pieces.
And although I'm a bit late to the topic, I very much prefer Vallejo Model Air acrylic-polyurethane primers. You can actually use a regular paintbrush to brush them on your models (so you won't need an airbrush), and it's very fast because the primer is very thin compared to regular paints. I find it almost as fast to brush on the primer than to use a spray can - and if priming only one or two models at a time, brush-on primer is actually faster because then I don't need to set up my spraying box on the balcony and spend minutes dancing with the spray can shaking it. The acrylic-polyurethane has worked very well for both Conan and Mythic Battles: Pantheon miniatures. I usually prefer black primer, but you can use grey or even white for a brighter, more vibrant end result.
I mix and match Citadel, Vallejo, Army Painter, Formula P3, Coat d'Arms and Reaper while painting - most paint brands have good stuff, and it mostly comes up to a matter of personal taste which brand works best for which task.