Thanks. So they also have a sizer for personal items? I'm assuming if I can "squish" the personal item into the personal item sizer, then it should be OK.

And one additional, but unrelated question. We have a tight (just under an hour) connection in DEN between flights, which is another benefit to not checking luggage. I see that both flights we plan on taking have awful on-time performance, which I'm guessing might be partially caused by sizing every passenger's carry on luggage. Does Frontier have a policy of holding a plane if they know that there are connecting passengers on a flight that was delayed - or do they put them on the next available flight to the destination?