Reviewers say they love the many heart-rate features included on the Polar RS300X, although you will need to buy the separate G1 GPS Sensor (*Est. $130) to track speed and distance. The Polar RS300X comes with a comfortable chest strap for measuring heart rate, and it includes a host of features that help users analyze their workout data. Reviewers appreciate the built-in fitness test, and users say they like that they can customize training zones and alerts. The display is easy to read, according to reviews, and experts say the watch is easy to customize.. The Polar RS300X is large, which may be a problem for those with small wrists, and some say the display is hard to read while exercising. Overall, reviewers prefer Garmin's GPS watches, which have an integrated GPS module, for tracking speed and distance. The top-rated Garmin Forerunner 210 (*Est. $200; $250 with heart-rate monitor) gets especially high marks.
A variety of fitness publications have reviews of the Polar RS300X, including BikeRadar.com, Women's Adventure and Runners World magazines. User reviews aren't plentiful, but Amazon.com has a good selection. We also found a lengthy blog post at FitSugar.com.
BikeRadar.com gives the Polar RS300X a 3.5-star rating (out of 5). Although the heart-rate functionality is top-notch, Nik Cook says the display is hard to read while exercising and the separate GPS pod takes a long time to acquire a GPS signal.
Review: Polar RS300X G1 Heart Rate Monitor Review, Nik Cook, Jan. 11, 2010
2. Women's Adventure magazine
The Polar RS300X earns an Editor's Choice award from Women's Adventure magazine. Editors love the included fitness test, and they say the display is easy to read and provides a lot of information at a glance. However, the watch is rather large.
Review: Polar RS300X Heart Rate Monitor, Editors of Women's Adventure magazine, June 8, 2010
Runner's World magazine recommends the Polar RS300X for exercisers who want a lot of heart-rate data. The chest strap is comfortable, testers say, although the navigation can be confusing at first.
Review: Time Machines, Mathew Honan, Jan. 2010
Nearly 20 reviewers comment on the Polar RS300X G1 (which comes with the GPS sensor) at Amazon.com. Most say the watch is sturdy and works well, although some users complain about finicky GPS signals.
Review: Polar RS300X G1 Heart Rate Monitor Watch with G1 GPS Sensor, Contributors to Amazon.com, As of April 2011
The editors of FitSugar.com say they love the lap-recording feature on the Polar RS300X, although they test the watch with the S1 foot pod rather than the G1 GPS sensor.
Review: Gear Review: Polar RS300X Heart Rate Monitor with Foot Pod, Editors of FitSugar.com, Sept. 30, 2009