Looking at many online steam shower units in uk and would like to know
if anyone has any advice/recommendations?

Fiat makes a nice set up. Look at
http://www.fiat.ca/viewProduct.asp?ID=18. Not sure if it is available
on your side of the pond though.

They also have some PDFs in there about steam showers and installation
in general.

-al sung
Rapid Realm Technology, Inc.
Hopkinton, MA