I have a '99 Specialized Allez I've spec'd for Triathlons. I'm upgrading my wheels and have a chance to get a Profile Carbon X Bullhorn aero bar (I'm using Profile clip-ons now) or an aero carbon fork. Both are $150 and I can't afford both.

Given that wheels will add speed what's the better use of $150 to further improve my ride? Fork over for the fork to complement wheels or go for the aero bars?

I appreciate your thoughts!