Never heard that about warranty issues. How would a company know if the robot was left in or taken out? They're meant for water so yeah, they get exposed to it. Skippy takes ours out once a week during the summer and checks the basket (empties).
Robots don't require high energy pump electricity so you save cash. They're easier to fix or even replace which makes them cheaper than IFCS. The brush the walls. What's not to love??
We've read many a story here by pool owners who hate their IFCS. Something breaks and its a pain. Or they miss areas entirely. Or they just don't work that hot. AND they cost a fortune! That alone makes a robot a better buy, IMO.
Maddie