Yes. If you are going to the salon and investing in a professional haircut and/or professional hair color you need insurance for your investment to keeping your professional color and cut looking it's best. The best way to do this it to buy these top notch, professional, products. It is important to purchase them from the salon you're going to.
You love your salon? Support your salon then. When buying the products from your stylist, you are getting professional hair care that is meant specifically for your hair situation. With a salon guarantee, you are actually getting what you are buying.
There is process to even be able to carry these products. We have to be interviewed to even be able to carry the lines of product that we do. When you buy from outside your professional salon, you don't know what you are getting in those bottles. There are plenty of horror stories out there about what can happen when you don't buy these products from a salon as there is no way to regulate what is in the product.
The bottom line is that you should be using top of the line products to support your professional haircut and color and you should buy these products from your salon, not only to support your salon but to ensure that you are getting the actual product you are paying for.