Garmin Forerunner 620

The Garmin Forerunner 620 is one of the best GPS watches our testers have ever used thanks to its touchscreen, fast GPS signal acquisition, and 41 data variables. The onboard accelero­meter gathers info on running efficiency (cadence, distance, pace), and with an optional heart-rate monitor, the watch can even predict race times, estimate V02 max, and suggest recovery intervals. It's the most powerful training tool money can buy. [$400; garmin.com]