You'll never regret buying professional grade watercolor paints.  Winsor and Newton is the brand I continue to purchase because of their reliable pigments.  I use them right out of the tube, but it's easy enough to buy empty 1/2 pans, then fill them and create your own watercolor palettes.  I'll continue to buy Winsor and Newton watercolor paints, because who doesn't love playing and painting with a new color?!