If the Hilton is what used to be the Sheraton, I believe same ownership that took Moorea and Bora Bora Nui out of *wood to Hilton, then that hotel is very close to the airport, but not as nice as the LM. If they're not the same, you can stop reading now.

Just before they switched, I stayed at the Sheraton overnight and was upgraded into an amazing suite with a direct view out to the harbor. There's no beach there, small pool, a nice breakfast buffet (again, this might've changed). The taxi service I'd used for the roundtrip to the airport forgot about my pickup to get me to my sunset flight to Bora Bora, so make sure you confirm it during the day. Were I going to spend longer on that island, I wouldn't choose that hotel, but for an overnight it's fine.

I haven't seen LM, except for when the 1/2 day tour bus I was on pulled into the joint to pick up additional folks on the tour. It's further from the airport, but nicer.