Some cats need variety. My Gabby would not eat the same food for more than a few weeks, or she'd get sick of it and refuse. I avoided this by rotating different flavors of different foods. Some she liked more than others--Merricks, Petguard, and Wellness ended up being the winners that were rotated frequently. She would not eat foods with liver for more than a week at a time.
I would get several different types of low carb canned foods, rotate, and find a few different foods that she likes. Then rotate those flavors around every few days. Even premium foods are going to be cheaper than what you're paying for the DM, so you have a lot of options.
If you're considering a food that isn't on any of the food charts, check the ingredients. Anything that is just meat--no corn, wheat, soy, rice, or other starches added to the mix, is going to be low carb. Most cat foods with gravy are going to be too high in carbs (contain starches and wheat gluten), and most pates are going to be low carb (all meat, no grains). If you want to try the special kitty pates, I believe all or most of those are low carb. Just check the ingredients on the label. If I remember correctly, the special kitty selects are the pouches with gravies, which would make them too high in carbs.
Edit: I just did a search and I see that they also call their Fancy Feast type pates in the small cans "select"--those would be fine to feed. If you have a cat that doesn't like liver, though, you might be better off with a premium food that doesn't have much liver, like Merricks, EVO, or Wellness. If you enter your zip code in the
store finders on their web sites, you can usually find them at local pet supply or feed stores for very reasonable prices--it costs me less to feed Bandit Merricks than Fancy Feast after getting a case discount at the local feed store. Wellness is even cheaper if you get it in the large, 12 oz cans, but I would get some small cans and make sure it's liked before buying in bulk like that.
