UA Mileage Plus would 'pay' for the same flights in eco:
500 status miles (for anyone), plus a bonus (not counting for status) of 25% = 125 miles for Premiers, and 100% (not status) for Premier Executives and 1K.
Even for paid first the status mileage credit would remain 500 miles, but a class bonus (not counting for status) of 50% (plus the 100% status bonus) would bring the mileage total for a Premier Executive/1K to a total of 1'250 miles.