I visited the Tokyo Citadines last year and was impressed by their room layout and thus decide to chose the Bangkok one as well.
Location wise, it is minutes walk from Asoke BTS station or Sukhumvit MRT station. If you taking the BTS to the hotel once you reach look for exit 4 or 6. Exit 4 requires you crossing a traffic junction toward Exchange Tower. I would suggest using Exit 6 which is a bridge link into Exchange Tower, go into Exchange Tower and take the escalator down rather than having to carried heavy luggage down stairs if you use Exit 4. Once down the escalator walk towards the Starbucks and exit the main door, go towards left and turn left on the 1st alley u see, u should be able to see the Citandies logo. There is also a Foodland super market 15m down from the Citandies which is great as it a 24 hour mart so food and water can be purchased there.
Room wise, it is almost identical to the one from Tokyo, a dry kitchen when u enter the room and follow by a small living and movable panel dividing the living room from the bed. It was bigger than the Tokyo one though. Clean and tidy all 4 nights of my stay, small episode of a lizard in the room on one of the night and the showerhead was not able to fixed to a position and kept sliding down and air-conditioner was a bit noisy during the night but bearable, just slight signs of wear and tear but overall still very good
Service was professional through out although perhaps I was expecting a bit more friendliness from the reception that is known for in Bangkok when we arrived initially.
All in all this a fantastic place to stay and very good value for money. The room provide more than the typical hotel room and is good for leisure usage and business. Highly recommended.