best gps/heart rate watch for ironman

I have seperate ones for the run and the bike at the moment.love the garmin forerunner 405, but have polar on the bike..both grand but few of u have one that does both properly??.(can use garmin on the bike, but has to be on ur wrist)..garmin runs out of juice after 8 hours, so unless i start breaking some records...any suggestions on what to look at/avoid??..

Garmin 310X and 405CX have a battery life of 18 hours. You should be able to finish the ironman in that time

310 is fully waterproof as well

They are both way more expensive than the 305 and the normal 405 though

If your selling the 405 let me know. My lady friend is in the market.

Seems to be a good review of the 310xt.
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The 405 doesn't have to be on your wrist, you can get a bike mount for it.

I was wondering the same.
I'm gonna use the 305 mounted on bike for bike.
Then gonna purchase a basic garmin HRM that I can enter my zones in to to use for the run. Would like to have a less bulky hrm for more general use anyway. You can pick one up for less than €100 online.
I replaced my 305 recently with a new one. Got the 305 new on Amazon for Stg£105 plus £7delivery. This plus a separate smaller hrm for running is almost half the price of the 310XT in town.