I am planning on taking a Y-DNA test. As a male myself, if there is an option to test my father or paternal grandfather instead, would there be any practical benefit? I am not inclined to test more than one of us, due to the cost.
My understanding is that the rate of mutation of Y-DNA is so low that it probably should not make any difference (i.e. we would all get the same results). Adoption or illegitimacy is not a concern here (autosomal tests already confirm the relationship to father and grandfather). I wonder if at higher level testing (e.g. Y-111, Big Y-700) differences may emerge within 1-2 generations?