Does it matter if you use the PvP staff or the one hander and offhand?
FOr shadow and disc..
Honestly, dont have a clue..
Edit: I mean is there a difference between using the two.
Yes. 1 hander / off-hand provides slightly more intellect, but with that combination you are forced into crit over extra spirit which can be bad for disc.
For shadow i'd say go 1h/ offhand for sure, for disc it's more of a decision.
Ruthless Gladiator's Energy staff -- 689 stamina, 460 intellect, 306 spirit, 306 resilience
Ruthless Gladiator's Gavel - 296 stamina, 197 intellect, 131 Crit, 131 resilience
Ruthless Gladiator's Reprieve - 384 stamina, 256 intellect, 171 spirit, 171 resilience (+40 intellect)
total -----------------------680 stamina, 493 intellect, 302 total rating, 302 resilience
Staff gains 9 stamina over 1h / oh, but 1h / oh gains 33 intellect. Staff also has 4 resilience and 4 total rating for secondary stats over the combo.
TL:DR go with 1h / oh unless your a healer that devalues Crit rating heavily. The intellect loss isn't worth it in most cases.