The free buffet breakfast option is excellent. They also have free tea with cake and fruits between 2:30 and five in the afternoon. Most people miss this, however, if you stay in Hanoi, this is a nice break in mid afternoon.
Hotel itself is very nice, very clean, just watch for the room they are giving you - as you may sometimes get worse room that you paid for which was the case with us during our first stay there before Ha Long Bay.
Anyways, overall well worth the visit and the money we paid for.
Also - very difficult to beat their view from their restaurant and sky bar:)