Tenchi, I have the GS merit ws, it's beyond awesome. Resolution does ridiculous damage. I'm also a Elvaan dark knighy with maxed strength merits and +80 str in gear, so I'm just under 200 strength for Resolution. With a Hoarfrost blade, I can average 2-3k on most Voidwatch enemies.
Tachi Shoha, the great katana merit ws, is equally impressive, but the damage is terribly inconsistent. I've seen guys do 4k, then out of nowhere...300 damage. It's odd, but still, it's some of the best spike damage a sam will put out, and you can make the magian store tp gkt for it as well.