What Perks do you want to see next?

So now that Demo and Firebug are confirmed and soon upon us. The question is, which two of the remaining four Perks you want to see brought in next?

Vote on the poll and explain why in the thread. The Poll is public so you should be able to see the voters on each Perk.

My own vote lies on Gunslinger and Helmet Guy. Just because I love going akimbo and Helmet Guy is so mysterious and full of potential.

What Perks do you want to see next?