I'm currently using a pair of SS Test Opener whiteouts, they're nice and comfy and have more protection than I'll ever need!
The lightest pair I've owned were a pair of SS Platino, the protection wasn't awful either so may be worth considering if you're on a budget.
Honourable mentions for decent protection and comfort go to:
GN Powerbow (circa 2005 I think)
Ayrtek
GM Original Limited edition
Online Stockist blank pads (they were small men's size which may be a deal breaker)