we stayed there for 10 nights in November 2007.
I definitely like the place.
Platinum treatment was quite nice indeed:
We were first upgraded to some SPG room. Quite nice and spacious. But I wanted even more and pushed (quite hard) for an upgrade to a suite :-) We were able to move 3 days later into one of the biggest suites I have ever been upgraded to. I am pretty sure this was the very best suite available in the whole resort. approx. 40 sqm terrace, large living room etc etc.. I think we also had the minibar included.
The Spa was being refurbished at that time so I can't say anything about it.
The club lounge is quite nice. Decent hors d'oeuvres, drinks like Gin, Whisky oh and freshly squeezed orange juice.
We also checked out the restaurants. The Japanese one and the Vivace pool restaurant were brilliant. Don't go to the big buffet restaurant where all the package tourists go. It's massively overpriced.
Staff was mostly professional and Sheraton La Caleta / the GM even sent us a Christmas greeting that year and the year after. Nice touch.
Stay was on points only.
Can't say anything about transfort from TFN as we flew into TFS which is not too far away. We had a rental car, though.
Hope this helps and enjoy your stay! (and please report back with some more recent experiences)