HRM

Depending on how much you want to spend, the Polar S625X would be a good fit with your CS600.  You could wear it for the whole race, it has foot pod for tracking distance on training runs, familiarity with Polar features since you have one, and the strap will work perfect with HR function on CS600. I have a similar set up with a CS200CAD and an older S410.  It's nice because once you hop on the bike, the bike computer will "take over" so to speak.  Hit your lap button in transition and you will have splits and HR data for all three legs.  Plus you will have the bike data on your CS600.

Nice Set-up.  Or you could look at the newer Polar's like the RS400 or RS800 series.  They just don't seem as robust as the S410, S625X models.  Others here on BT may be alble to give you more info on those series.

Thanks I will give those a look.