Just bought (finally) my copy of GW2 now that summer has started. What will be the best use of my time during the stress test?

I am so pumped for this stress test!

So what will be the best use of my time on the test? I imagine I cant get any leveling done. So I guess maybe PvP or WvW will be better?

And if it helps, I am going to try warrior.

EDIT: Thanks for all the tips! I think trying sPvP is what I will focus on. Hopefully I might try a little WvW though.