Thank you very much for your answers.
When you have booked a refundable room directly at the hotel site do you also use afterwards the hotel compare sites such as kayak or tripadvisor ?

The problem which I see now is that amoma , getaroom,otel do have prices which are too good to be truth.
When a market price will be $145 for instance they offer the room for $55.

So I do use priceline and hotwire a lot and I save a lot off $ but I use them the most for 5* Hotels.

Are the big sales off Hilton always at December which I do use once or are there other fixed sales periods ?