I would like to put in a couple of words in this topic .
I have bought quite a few bikes From David Silver lately and he is very nice to deal with . I ask for a discount and some times I get it and sometimes we do manage to arrange a price . Lets face it he does know the market . Also in my opinion as already mentioned his bike prices I think are more realistic than other sellers .
Also as for for after sales they can be very reliable in my opinion from return of parts , to even help getting an original lost title.
You sometimes mention that he does not offer free shipping on parts , that is true but at least normally it is a fixed price. Also imagine for us abroad the shipping cost is much more expensive !!
Uli should you go ahead and be interested in a particular bike , just ask them for more detailed pictures and any history that they have about it and I am sure that they will fully co operate and help in any way possible.
The above is only my personal opinion from the experience I have from dealing with them.