Ironman 70.3 Calella (Barcelona)

I will participate to Half Ironman Barcelona on the 19th of MAy. As the bike course is basically three climbs and downhill and no flats, I was wondering if it is better to bring the tri or road bike.
Any suggestion?

Friend of mine who is a top 5 AG athlete is taking her TT bike. I have a feeling that it is like Rapperswill Jona, if the descents are not to technical, and you are comfortable maintaining 50-60kph the advantage of being on a TT bike is massive

Thank you. I have checked some videos on YouTube and it seems indeed that downhills are all non technical a pert from a few km. I have finally decided to ship my tri bike.