If any of you are looking for a great leather cleaner which is easy to use and works extremely well AND which does not make your leather shiny, my recommendation is to use this stuff:
Gliptone Liquid Leather
It really is one of the very few products that I have found which gets your leather looking new by keeping it matt rather than shiny.
In particular, I use the 'GT12 thick concentrated gentle cleaner' every few weeks to give the seats a 'deep' clean and I use the 'GT15 trigger spray cleaner' almost every week just to keep on top of the everyday much that builds up - especially things like blue jean stains which is a nightmare on lighter leathers but can even make black leather develop a shine over time.
They even do a triple pack with a conditioner for £23 but I've never felt the need to use the conditioner (don't keep my cars long enough for it to matter!).
Just ordered it!! Thanks