Trek TTX vs. Felt B2 vs. my bike

The Trek Equinox TTX 9.5...... soooo pretty, and so fast looking. My other option: the Felt B2

How is a girl to choose?

(Just to clarify, my options have been narrowed to these two bikes given that I work at a bike shop where these are the tri bikes available to me....if Cervelo was available I'd be all about a P2C)

And then there is my poor beat up little Giant road bike:(I was working on my super speedy aero position that day....it needs work) If I had one of those other bikes that probably wouldn't be so hard to achieve.

So how do you decide whether to put nice wheels and nice accessories on a road bike that works okay for triathlons, or get a fancy new tri bike that can really only be used for tri training and racing or time trials. Is it worth the money? How much faster will I really be? Can I sit in such a tight aero position for that long? Look at me in the photo, I'm down, but I'm not that down...look at Michielle Jones....

Yup, I have a long way to go. But look at her bike! SO sweet. Decisions, decisions.