As a non-donor SK tank, the Dark Sword of the Vampire Lords(webtools/items.php?id=99358) is the first real upgrade from the sleeper's tomb Sword of the Master (webtools/items.php?id=11920).
Obviously being a DSK weapon compared to a Sleeper's Tomb weapon, it has much stronger statistics. However one glaring difference on the two weapons is that the Sleeper's Tomb weapon procs a rune buff that effects the group. This is fantastic for aggro, and while it may absorb less damage than the rune on the Dark Sword of the Vampire Lords the threat it generates makes it vastly superior.
When it comes down to tanking, the weapons primary role is for threat and less about survivability. The rest of your gear brings your survivability. While the weapon offers some as well that is not its primary focus. As a result it makes it really hard to warrant upgrading a sleepers tomb weapon for a DSK weapon.
My question being is it possible to change the DSK sword into a group rune proc like the sword of the master? This would make it a much more enticing upgrade, and make me feel less obligated to use a weapon from 4 tiers below.