Join Date: Dec 2002
Location: Danville, CA, USA;
Programs: UA 1MM, WN CP, Marriott LT Plat, Hilton Gold, IC Plat
Posts: 17,987
There is no reason to check it with the regular baggage unless you have some reason that you don't want to bring it on the plane.
In the event the flight is 100% full, you can simply gate check it as you board, and it will be waiting for you at the ramp as you exit the plane. Much less chance of loss or misdirection... we do it this way every time.