Agree, robos won’t fall in and drown
all that’s needed when using a bowl is a bit of common sense ie not an enormous bowl, and put somewhere where it can’t tip. It is better for hamsters to use bowls, most do prefer them and they are more hygienic.
The silent runner is also fine for robos, that or the wodent wheel would work. The runner spins a bit easier and is probably a bit better.