The event box pleat style dates to the late 18th century, the misnamed 'military box pleat', which Bob Martin referred to as a box-knife pleat, dates to c1830. Neither is "correct' for period (mid-18th century) re-enactment. Which you choice to wear is a therefore a personal preference; my own is for a 5yd box-knife which a like because it affords the option of a narrower box and slightly more weight in the pleats.