The Porchester Spa Queensway, London, W2 5HS Nearest tube/overground: Bayswater, Queensway or Royal Oak Tel: 020 7792 3980 Hours: 10am–10pm, 7 days a week. Men only: Mon, Wed, Sat. Ladies only: Tues, Thurs, Fri. Expect to pay: £20.35 for admission (£11.55 for Westminster residents); any treatments are extra Rating: 8 out of 10 Behind an unassuming set of West London doors boils the Porchester Spa, an Art Deco palace of heat, steam and sweat.......