I'm with The Souljourner and Marshall on this one.
I'm having some fun with my Dwarf Bbr4/Rgr4 with the Power Attack, Improved Shield Bash, Shield Expert feats and a Shield of Bashing.
He isn't the greatest melee combatant of all time, but the extra +3 to AC and the chance to bull rush someone 5ft every time I hit is useful.
I'm looking forward to the Shield Charge feat at 9th level - then my DM might start to freak out at the double damage from a power attack charge when raging <grin>
I gave it a 7 - not for everyone, but great for TWF types who need a defensive boost.