I love it because it is a fully renovated, old, traditional place with extraordinary atmosphere. The best time for visiting is the Night-bath Session from 10pm until 4am on Fridays and Saturdays. Inside there is a drinking hall, the water of the springs Hungária, Attila and Juventus can be consumed for the purposes of a drinking cure.
You should visit it to experience the stunning view of Budapest from the rooftop jacuzzi. I think this will gives you the feeling to fall in love and to come back year after year. Just imagine these details: The centerpiece Turkish bath was built during the 16th century in the period of the Turkish occupation. The sauna was built in 1936.
For inside pics look at this blog post: http://www.spabook.net/index.php/travel-tours/item/24-rudasbathbudapest
Mon-We: 06:00-18:00
Th-Su: 06:00-20:00
Fr-Sa: 22:00-04:00