Mitered Box Top w/ Flush Panel

I’m looking to make a box with a solid wood panel top that is flush with the box top sides (like this one http://lumberjocks.com/projects/21003 ), but I’m concerned that such a snug fit would pop the miters if the top expanded at all. Is this a logical concern? The only other option I can come up with is veneering a thin sheet to either mdf or plywood, though I would prefer to avoid this since my bandsaw is limited in its ability to cut wide, thin sheets. Thanks.

-- Dan Chiappetta, NYC, http://www.9x7woodworks.com