D.,
I did not see your original post and I have not used Planetbox, but I have used all-in-one type containers like it. While it is cute and convenient to buy a bento set or all-in-one, I have not found either to be great for school. Your kids might be different and perhaps the all-in-one style I had was not great, but something to consider is that if you pack something more strongly scented than other items, everything will smell like it (tuna fish, liverwurst, eggs,....) or if you have something really moist it can make chips or cookies soggy. Also, I over pack my son's lunch so he can have a little selection at lunch. As such, I was always throwing food away from the all-in-one. I currently use a regular insulated lunchbox of his choosing (last year it was a cool retro tin lunchbox) with several individual plastic/stainless containers of various sizes. This way, if he does not eat his chips or fruit one day, I simply put the unopened container in the lunch again the next day. I know the individual stuff seems like more work, but in the end it seemed to be just a little more effort than the single piece. In any case, it would be great to have a follow-up on what you chose and how you liked it.
C.