I use Chefmaster, as they're more readily available here and I find they have less aftertaste than some other brands. I prefer their large 4 oz (ish) container with a dropper top, as the color is much more easy to dispense than in a lidded jar - and easier to create color formulas by counting drops.
I just looked up Chefmaster and the coloring is reasonably priced. Do you use the liquid or the gel?
I use the liqua-gel with dropper top, which is actually a 2.3 oz (not 4 oz!) container: http://www.bakedeco.com/detail.asp?id=4409&categoryid=511#.UozdG9KsiSo
I also use their airbrush colors.