The Ultimate Hammer (like the ultimate bow thread =P)

I recently posted an axe on the price check section but I decided to keep it myself since it probably wouldn't sell for much. So far, it's a Cruel Hammer of Fortitude, and I'm definitely going to get rid of the "Cruel" part of it.

Would it be better to get a vampiric hammer (4:1) or a sundering hammer (+10% armor penetration/10%)?

Vamp gives definite damage, and heals you, while sundering is hit or miss.