The lounge is nice, the massage is a bit special. But then the private rooms are not private - they open to the main lounge area and are quite noisy (you hear all the announcements from the terminal since there is no real wall to the main terminal. Food is limited and edible, but nothing to write home about it.
The lounge is nowhere near what LH offers in FRA/MUC, LX in ZRH, AF in CDG or CX in HKG.
If it is your first time and you can get the massage then the recommended 3 hours is already plenty.