I stayed at the Sheraton Gambia for 1 night a few months ago. My experience was not any different from 365RoadWarrior's post in 2011.

You get what you pay for. Rooms were somewhat clean, wifi was ok, pool and beach area were quite empty when I was there. Breakfast was buffet, but with limited quantity of food. Hotel area is quite isolated, I didn't find any restaurants or stores nearby, just residences.

Took taxi to the market, and think it's around USD6-8 for a round-trip, there are green taxis parked on the hotel.