I wouldn't consider staying at either of these properties unless I had to.

The Sheraton was built as a 3 star Outrigger, and has nasty, small rooms, and exists largely as a venue for the Tahitian elite to socialise at weekends and for cruise ship passengers to have a short transit rather like yours.

Meanwhile Le Meridien is a really good hotel, but takes AGES (and $50 more) to get to at night-time, and up to an hour to get to the airport during rush hour.

If I desperately needed the night / stay credits I'd go to the Sheraton. If I was staying several days I'd go to Le Meridien.

But if I had a short overnight stay like you, I'd probably go to the Beachcomber Intercontinental. It's a great hotel.