So I only started doing arena this season last month after taking a break from arena since season three and over the next three weeks I'll be picking up the pvp dagger/offhand/wand and I couldn't come to a conclusion on which would be a better combo. I wanted to see what other higher rated locks think.

First would be with Lightweave and I would be running 126 spell penetration with an extra 38sp and the proc for 250sp for 15 (295sp after 3.2) or keeping spell piercing and using four sp gems which would put me at 141 spell penetration and an extra 76sp. :-\