I stayed at this hotel for a week at the end of March while attending a family funeral, so my review is not from a holiday makers' viewpoint, however I found the hotel very comfortable, easily accessible from Faro airport, helpful, very clean and well presented - in the mould of a higher end business/conference hotel. The beds are great, the breakfast is quite extensive and delicious - particularly the coffee! The spa area is lovely and the staff I found to be very friendly.
I wouldn't get too hung up on the star rating; what constitutes a star varies from country to country I believe and is quite subjective - to me 5 star would imply near perfection and this hotel is not without it's small niggles and flaws, as described by some other reviewers, but it is a very good hotel and I had no complaints, especially as I found a very good deal online for a seaview room with balcony. It's worth going for the seaview, as the view from the other side of the hotel is a little bleak.
Olhao and the surrounding areas seem lovely and I'd love to come back one day to explore properly - I'd certainly be happy to stay at the Real Marina again.More