I have the same sort of problem with a 6/8 Giessen & Forsthoff. Bought it in the US for some reason 2/3rd of the price to be paid in Germany. The razor does not obay me. I don't manage to hone/strop the razor to the point that it is able to give me a smooth close shave. All the others (from (B)reidohr to (W)ade & Butcher and the brands with a first capital letter in the alphabet between the B and W that I own, from near wedge to full hollow) perfom the way they are to do.
And the problem is that I won't give up. The G & F is a razor that keeps on challenging me. I'trying to tame the thing more often than once a week. I'll strop it until I drop. When the latter happens I'll strip the blonde horn scales, bury the steel in my yard in order to dig it up it up a few years later and sell it to an antique vendor as a rusty cultural heirloom. I would't dare to let it lose on Ebay.