I managed to buy some Dermatch here on line and have tried it a couple of times.
It does seem to work better for the hairline than nanogen and combs through quite well with a wide tooth comb or brush. You must not use too much or allow the applicator to touch the scalp. However, I found that even if this happens a comb can rectify the situation if you make a small error.
I think combined with Nanogen further back this is the best result out there, for me at least.