I just found out that there are cat allergy kits you mail in with either saliva or hair. The prices range from $90-$250, depending on the test. This seems like a faster and cheaper way to find out what my cat is allergic to in his food (considering how long & the cost of food trials). Has anyone used any of these kits? If so, which one did you use, and was it accurate (did you change your cats diets based on the results & was it successful in eliminating the diarrhea)? Thanks for any feedback.