Sean I always purchase directly from Blicks website, for some reason the Blick catalogs have higher prices than the website...I'm thinking about going with the Blick color pencil as the cores are pretty much the same as Prismacolor and are much cheaper. Although I will still purchase the Prismas that are a must in my portraits, I'll look into the Blicks other colors that are used for everything that is not flesh tones. I buy open stock and only when I am trying a new brand I'll purchase the sets, after seeing what pencils I use most in the set, that dictates what pencils I buy in open stock. Last years inventory of color pencils was at $700 that was about 590 pencils, since I worked in oils quite a bit last year, this years budget is not nearly as high but will stock up on the pencils anyway and buy more paper.
But before purchasing from the catalogs always check out the website for a better deal and always look for when they have free shipping deals that are going on.