Personal preference will win out. I will say that if I PvP as Holy, I'll definitely have Body and Soul as well as Angelic Bulwark. It'll make PWShield a definite always use when it's up spell. Especially if you consider the PvP 4set. Going through the motions of a typical arena match in my head, I'll get more bang out of that than Desperate Prayer. I'd still have GS, HW Serenity on a much shorter CD, and Renew.