I'll have a go at answering your questions:

1. In terms of mosquitos, I imagine that this changes a bit depending on the season, but 'how bad are they'?

We hardly noticed them. The ones that bit us did so without our realising. I have four bites and partner has seven. However, we are pretty sure that only one of those was while on property. The others were during the walk around the island when we had stupidly forgotten to apply insect repellent. The resort, including each villa, is "fogged" daily to keep down the mosquitoes.

2. Does the outdoor toilet feel like an outhouse or is it a nice feature?

Yes, to both!

3. How did the menu look, and were there a lot of choices including non-meat options?

We paid attention only to the vegetarian options, so I can't answer for the rest of the menu. There is "My Grill" restaurant that specialises in seafood and steak next to Tonsai that covers Thai and Italian. Z-bar does bar snacks until 21:30 and there is 24-hour room service. The Director of Food and Beverage told us that they were pretty much all vegetarian as Six Senses so the chefs have lots of vegetarian menus they can use, and to ask for anything we wanted. It would be nice if they could put together a list of these options, as it somewhat ruins the dining-out experience to dictate to the chef what you want.

4. Did you get any impressions on how they changed the facilities from the previous incarnations as Six Senses?

We thought the property was new. It came as a surprise to discover that it had been operating for three years. No idea what has changed.

5. Was there any of that health-retreat vibe or activities left over from the previous incarnation?

The resort feels like a place to luxuriate rather than keep fit. I can't compare to what went before.

6. What were the activities available, if any? Would 4 nights there be 'too-much?

There were plenty of day trips available, many using the hotel's speed boat, but similar trips are available from the hotels on Phuket Island for a fraction of the price. If you want to see Phuket or do boat trips, I would base myself elsewhere to do those. There were a few water sports options, but they were all at extra charge so I didn't pay attention. I wasn't aware of any resort-style activities, but this isn't that sort of place. You would come here to chill primarily and enjoy the beauty of the place. Whether four nights is too much would depend on how long you enjoy reading, relaxing, sunbathing, swimming, etc. My threshold for these things is pretty low, but I could easily manage 2 to 3 days here. I think a lot of people would enjoy longer.

7. Do you think a day trip or two to phuket town is manageable from the resort?

Easily possible, but expensive from here.

8. Were the villas updated, or newish looking inside? Would you consider them luxury or spartan?

We thought they were new!

9. How do you think this property compares to more expensive villa options on Phuket?

Don't know.

10. How were the other aspects of service that you encountered?

Not sure what you are asking. Service was good throughout.

Any pics??

Will try and post when I've had chance to download them to my netbook.

Hope that helps.