Entry height beats “senior friendly” marketing
A self-cleaning box can reduce owner workload while still being physically demanding for the cat. Measure the vertical step your cat currently uses comfortably, then compare that with the robot entry. A wide opening does not help if the cat still has to climb much higher than it does today.
Neakasa M1 Plus uses an open-top format, which removes the enclosed-globe issue, but openness is not the same as low entry. Litter-Robot 4 has a 15.75-inch square opening, yet the cat still steps into a raised globe. If mobility is the concern, evaluate the actual path into the litter bed rather than the opening width alone.
Minimum weight affects automatic cycling
Automatic boxes rely on weight or proximity sensors to decide when it is safe to cycle. Manufacturer minimums therefore matter. If a small or frail cat falls below the approved automatic-mode threshold, follow the manufacturer’s kitten/light-cat instructions instead of assuming the sensors will behave normally.
The practical consequence is that a box can be physically large enough for the cat but still unsuitable for unattended automatic cycling. That distinction is easy to miss in buying guides focused only on dimensions.
Use a backup box during transition
Older cats are often more attached to familiar routines. A new robot should not replace every familiar toilet option on day one. Keeping a conventional low-entry box nearby reduces the cost of rejection while the cat learns the new machine.
If the cat begins hesitating, eliminating beside the box or showing a sudden change in litter-box behavior, stop treating the purchase decision as purely mechanical. Product fit is only one possible factor; pain or illness requires veterinary evaluation.
Best decision rule
Choose the machine with the easiest physical access your cat will actually use, not the one with the most automation. If two machines are close, prefer the one that lets you disable automatic cycling, run supervised cycles and maintain a simple manual fallback.