I have been using the Polar HR RS200sd (red with foot pod) for the past couple of years. I like it... a lot. The battery on the chest strap died recently and the watch battery is about out so I bought a new one (black instead of red).
I've had a few runs with the new watch and I'm just not sold on it like I was the previous watch I wore for many training runs and races. I'm thinking the calibration is off, but how much difference can the standard 1.000 and my old calibration 1.010 really make?
I don't want to obsess about this, but I can't help it. I ran a little over 5 miles this afternoon after work and felt like I was at about 7:30/mile pace. Not too tough, but not too slow either. However, the watch was about 15 to sometimes 30 seconds off that pace. Not a big confidence booster.
So, Wednesday night I am going to be manually calibrating to see if there is any difference. I hope to come back with a better feeling than I have now.