Thanks TaoCow and Scotty,
Scotty, you say having your attention at the dan tien is better than at the nose. Why do you think so? Do you know if there are any budhist schools in London that have the dan tien as their main point of focus? I like to meditate but I also like to meditate with other people sometimes. This is one of my reasons why budhism is interesting for me. There are many accesible schools around. I have not come across any Taoist 'groups' in London, but that might be just me.
TaoCow, you say it's fine to combine both practices. I have in fact already done some experimenting and when I do practice mindfulness and dan tien meditation after each other I feel a very strong energy current in my head and nose. Something that was not so strong before I only did the mindfulness. Almost to the point that it feels almost like a head ache. This can not be right, can it?