Been going to King Spa a few times recently. I'd say if you like to sit in constant steam go to Island.
I noticed last two visits at King Spa even the old asian guys were annoyed, the steam would come on for 2-3 mins turn off and all steam go away then 5-10mins later it would kick back on.
This weekend this old asian guy got so annoyed, he filled up one of those buckets they carry in with cold water and dumped it on the thermostat when I walked in I couldn't see anything and It felt really nice with the steam but that is only way to get it to run enough.
Would be nice if they had a button like Island to get it to kick back on.
So in this case if you want to sit there and enjoy the steam, Island is your choice.
But for authentic themed Kspa King Spa is like it. Island is too commercialized if you want like the total asian vibe. The Co-ed at King Spa walking around it feels like one moment your outside in Jersey and now you are in Korea.
Just do not get lost 😂, i remember first few visits i had years ago i went down stairs and forgot where the upstairs was again for mens area.