Mercure Hotel. The room is spacious. No bathtub but there is no need for one when you are at Bangkok because massage and spa are all around.
There are universal plugs so not a need for adapter.
The view from my room
The Swimming pool
The view from the swimming pool
The difference between Mercure and Holiday Inn is the room size. Mercure room size is bigger and spacious. It has only a swimming pool at the top floor which is free for people staying at Mercure.
The best thing about Mercure and holiday Inn is that it is just beside the train station and there is an escalator going upwards. It is good for people who intend to take the train and not the taxi.