Those nice people at Lex Hatfield made up for me a load of the 'trade' stuff they use to clean the leather seats in my GS. Seems to work well but i want to condition them after cleaning. The colour is Andorra Grey and I am worried about using something which will darken them.

Any advice?

Try Frost Auto Restoration products. They are in Rochdale, but have worldwide postal service. I have tried their products, they seem pretty good. You should be able to find them on the web, I forget the URL. Dont think there will be a problem with darkening, not in my experience anyway.

[url="http://www.frost.co.uk/acatalog/Index_Special_Offers_5.html"]Frost Auto Restoration Website[/url]