So remember to leave the bedroom window open at night and not to have nylon bedsheets.
I think 20 hours from a Garmin 310 is very optimistic. The training partner is quite motivational but if you are over ambitious with your target on a regular basis it can mean that you train too hard.
Big advantage of the Garmin 310 is much longer battery length and you can download training schedules to the watch.
No point rushing these decisions but remember the old saying "Buy cheap, buy twice".
I think the original poster now resides in an old folks home.
Just what I was going to suggest Chris.
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