Great bag pack!!
Haven't traveled with it yet but plan to in 2 weeks. If you want to use it as a bag pack, the 42L is slightly bigger, 35L would work fine depending on the requirements but this is great as a carry on size and switch to big bag pack.
I am not super thrilled about the colors or the free pack I received. I would prefer to have an option to pay a bit more to get the desired color for the free pack.