Automatic Litterbox Central

I've been thinking about ordering a LR. I have 4 cats and this sounds like the answer to the constant litter box chores. My concern is that one of my cats is on the big side, vet weighed her last week and she was 21.6 pounds, will she be able to get in the LR and move around?

My Bengal comes in at 20 lbs. He could fit in .... barely but tended to make a mess digging.