The smallest is the Gate Sauna. The crowd is bears and older men mainly. It has a nice jakuzzi and a large cruisy steam room. You’ll have to pay extra for a proper cabin, but some basic rooms can be used free of charge. There is also a sling and a small dark sleeping area.
The most mixed is Apollo. Provides everything and the upper level is nicely renovated. The lower level with the cabins could do with a little spruce up, but nothing to complain about. They have several theme events so check out their site for what is happening.
The newest and biggest is the Boiler. Very modern, very big. It has everything a boy could wish for. The crowd is a mix between young and fit . Very nice wet area and no extra fees for cabins.