I found it not to be leak proof
There is a gasket around the perimeter of the bowl, and it there were no leaks from that. What is called the "quick release gasket" is the issue. Water will leak from that if the bowl is on its side or upside down. Worst case you could put a food grade sealant in the holes, as I don't see much purpose for the quick release gasket. If that was sealed up, it would be significantly better in terms of leak resistance
The locking tabs must be lined up properly in order to function, and they are not very strong.
This product could be improved by making the locking feature stronger.
The clips have already popped off a couple of times, so I'm going to have to be careful where I put the set. I can see the clips coming off in the car and water and food spilling everywhere