arrived very quickly and it is a fun little backpack. My daughter is 5 and she loves the colours because it is so bright and unique. I like too because she is easy to be spotted in a crowd (she did not want to go with a typical girlie girl backpack colours :-)).
 The backpack has a chest strap but the only thing that I was surprised not to see was a waist strap on it that would help the kids wear it better especially on a field trip.
Regarding the lunch pocket: it is insulated but because of the size of it , even if I included 2 average size gel packs in it, it did not keep the food cold for more than 3-4h which is enough if it is purely used for going to daycare and having the lunch kept in the fridge there. I believe though that 2 gel packs it is quite a high number of gel packs to include in a preschool lunch bag(it adds weight too) as I usually use just one for 3-4h  on my adult lunch bag so I assume that the preschool one doesn't insulate that well.
So  the lunch pocket can  be used purely for school if they have lunch there and not for a field trip where you need the food to be kept cold for longer most of the times because there is no fridge to be used....
Overall I am happy with the purchase especially that it has almost all the features that I wanted in a preschool backpack.

Updates:
I have had the backpack for 3 months now and  it broke down at the handle already...The fabric that  holds the back of the backpack to the handle came apart and soon it will not be suitable to be used ...
So sad and disappointing..
It was too expensive to ship it back internationally to have it fixed or exchanged but O3 company was willing to ship me a new one without getting the  damaged one back(I just sent a picture with the damage to them).
I am very impressed with the high level of customer service and I have no hesitation to buy from them again....