I've been pretty happy with the quality of Griot's chemical products, pricing aside. (It is mostly true that you get what you pay for.)
Their 'invented here' products are usually top-notch and innovative, but, as was the case with Sharper Image, for their 3rd-party products, I have been able to find them from other vendors at prices that are ½-¾ the price that Griot's charges -- it does take some sleuthing, however, and you don't get the convenience of Griot's one-stop shopping and fantastic customer service.