This review is based on our very recent 11 night stay at the resort. This is my third stay at Bali in this area and the "benchmark" is other five star hotels in the area such as the Oberoi, The Legian and Four Seasons.
The resort is new and the design is modern and elegant. evrything is clean and tidy, but there is no Balinese charm. Interior designs are more modern-European (neon light lit up bars, etc) than the more traditional upscale hotels. This is a matter of taste, of course, but it comes across as "wanna be hip" more than stylish.
We sayed in a one bedroom villa which was fantastic. Nothinfg less. No flaws -- all perfect.
The music crancks up, Hotel Côstes / Cafe del mare style at 4 PM and will, for some be cool -- for others annoying, in particular since the different resdtaurants / bars plays different music cathing you in the middle. Röyksopp for your right ear and some other lounge music from the other side.
Service is very good, but since the hotel is rarther large it also becomes impersonal. Staff are well trained and know what they are doing, but if you want true personalized service this is not the place for you. It feels, and is, impersonal and cannot be compared to smaller five star resorts in the area.
Dirnks and restaurant charges are resonable for a luxury resort. Wine prices are an issue in all of Indonesia, but in many hotels and restaurants they have thus not chosen to cranck up the already stiff prices on wine three to four the price at the wine dealers. So not the case with the W resort. Food is overall of high quality, in particular breakfast. I will rate the resort's restaurants in separate reviews. (Woo Bar, Fire and Starfish Boo restaurants.)
All in all: A great resort, but a bit lack of the charm found many other places.
A final note: the beach is great for adults, but cannot be used by children due to the strong currents and big waves. Flags were red all 11 days during our stay and hotel staff did not recommend swimming or bathing. The walking distance to other slightly calmer spots on the beach is relatively short and thus not a big issue unless travelling with young children.