Spent a long weekend here with the wife.
Amazing dinner in the restaurant, service could be improved but this is the only negative. Make sure you book a sea view as the room we had was a little disappointing, but you get what you pay for, never thought to request. The spa, pool and beach are fab.
Taxi from the airport was 45EUR. We ended hiring a car as it was cheaper than a cab and gives you the flexibility to get out and about as it's a little secluded. There are some amazing beaches close by and Olbia is worth a visit.
Free bike hire is also a good option to get you into Murta Maria (up hill pushing maybe required) for alternative lunch and a cheap coffee/beer/Supermarket. Tap water cannot be drunk in Sardinia and bottled is expensive in the hotel, so we used this option to store up the mini bar. More