We spent 6 nights here, just before Easter, and although it's pricey we really enjoyed our stay. Our kids spent hours in the pool each day. The pool itself is beautiful, and in early April was quite warm. The poolside is a sun trap and is very private, considering that you're in the middle of a golf course. The accommodation is spacious, clean and well maintained. Probably best enjoyed if you can go as part of a larger group and rent the flat above.
Playa de Santiago is a great base to explore the southern side of La Gomera with a really relaxed sun soaked feel. We would definitely return again, hopefully with friends!