Speedo friendly saunas in London?

[ESfan]

Hi Guys, my first post here

I'm a big speedo fan and I'm planning a trip to London. I'll be checking out some of the shops in soho to add to my collection. I'm also pretty curious to go to a gay sauna for the first time. What I'd like to know, if anyone can help, is which saunas in london allow you to wear speedos? I know some have very strict no clothing rules to minimise drug problems...

Thanks!