I just got it from ShutterCentral today. Fixed and used it over family dinner at ECP.
Great handling and gives me more grip. It works perfectly fine with one or two original or 3rd party Phottix LP-E5 or 6 AA alkaline batteries.
If fit two LP-E5 together, the power will be transmitted together in parallel. Anyway, I also gotten 2 x Phottix LP-E5. It's now double upon double of power for my 450D.
:bsmilie: Enjoy your battery grip. You'll find portrait more interesting than without grip.