Unfortunately, we won't be able to do this for our flight. ? I checked the Icelandair luggage requirements, and the under-seat personal item cannot be more than 5.9 inches deep! Here's the specifics:
All of the under-seat bags on the eBags site and Amazon are at least 8" deep, even ones that don't have rollers and are just a regular mini-duffel or small backpack.
Further complicating the issue will be the fact that my younger daughter and I will both be carrying our cameras / camcorders with us in their travel cases. I plan to put my camcorder inside my carry-on bag so that I can still use my ultra lightweight fold-up backpack as the personal item; it will hold things like the still camera and filters / accessories, headphones, iPad, etc. I'll probably advise my daughter to also pack her camera bag in the carry-on so she do the same with a satchel purse or the like. My wife and daughter will probably have their purses as their personal items; there is no way they are traveling without those!
I'm starting to think it might just make sense for each of us to pack a second carry-on size suitcase (we have a few extras), or maybe we pack two extra checked-size suitcases (one for me and the wife, one for the kids; again we have some extras now), and I'll pre-pay the charge for the extra bags. Will see what others recommend before I bite that bullet. The cost for extra checked bags will still be less than buying actual new luggage for all of us.
Yup, we bought one of those before our first cruise to make sure we didn't go over the limit on our United flights. Have brought it on any trip requiring flights since then.