I have a question on the personal item sizer. For our upcoming IAD-AMS trip we plan to take the eBags Motherlode backpack as the carry on and one Red Oxx Gator and one rolling tote for the personal item. The tote measures 14"w x 9"d x 14"h.

Technically this makes the bag 3" taller than their guidelines but it fits under the seat with no problem. Are we OK to take this or will it maybe get flagged to be checked?