Well, our oldest cat Diablo developed diarrhea and so after doing some research on cat nutrition found that we were feeding an inappropriate diet of dry food. I found out that wet food is much better for cats because they get up to 80% of their moisture from their food and they have an inherently low thirst drive, which means if they are on dry food they are in a constant state of dehydration. Diablo finally ended up developing an allergy to all of the grain products in his food like corn and soy and wheat.... SO....
I have moved them over to grain-free canned cat food and have seen a huge improvement in Diablo's output (plus a softer, shinier coat!). Nice formed stools, no more diarrhea sprayed all over the girls bedroom rug or the hallway carpet runner. It's all in the litter box where it belongs. BUT, grain-free canned is EXPENSIVE! The cheapest I can find it is 1.09 a can, unless I get the large cans in bulk, which drops the price to 95 cents per can. Now, only Diablo needs the grain-free, so if I keep Azrael on regular canned and Diablo the pricey stuff, the least amount I will spend would be $45 per month.
After having investigated the raw diets, I believe I can feed them for cheaper using raw meat/bone/organs with some extra supplements added for cheaper than feeding canned, and the raw diet will be much healthier for them. The meats need to be sourced still, but if I can find good clean meat at good prices I'll be set. Then I can grind everything and add supplements or see if my cats will eventually go "whole prey" style. Throw a rabbit leg or ribs or whatever on the ground and let them go at it. Or a whole rabbit! LOL
I've got lots more research to do! :)