I have 2 litterboxes and 2 cats. It's working fine so far.

They get Purina One sensitive systems dry (I give them a spoonful each of el-cheapo canned mixed in once a day)

Strictly indoors (although I ocasionally put a leash and harness on them for brief forays outdoors)

My cats are not currently declawed but I'm not against it. There must be a good reason for it though. My last cat was declawed when I adopted him. My current 2 don't scratch on anything they're not supposed to, so it's not an issue. I just trim their claws about once a month.