i was in Target yesterday looking at the same sterilites. From my own experience, the gap between the top of the tub and the plastic housing is way to big. I put my hand in the tub and could easily push my the pinky finger between the gap. Plus the plastic tub is real flexible and gives way too easily.
I did a test at home with one of these tubs and my 3 month old lesser squeezed out without any problems. Unless you can find a way to close the gap and make the tub less flexible, I wouldn't chance it.