It is great experience in Halong Bay.
I strongly recommen to visit there.
It is quite long journey from Hanoi.
So, it is happy choice ; one or two nights.
I stayed one night.
Whatever the tight scheduled activities are all very nice, but if the guset join all schedule, then it may have less time for relaxation on board. So it is all your choice either.
And up to guests , there is good chance to meet nice people on board.
The room is small but very well equipped and super comfortable.
disadvantages:
The food except four meal is not sold on board.
Naturally, the drink is expensive compare to its cheap price in Vietnam.
Please must prepare US dollar not VDN.
Even they are all kind staffs, some of them don't speak English.