Using the Polar RS300X is like having a personal trainer on your wrist. Its Smart Coaching features track and measure your fitness progression, and keep you on target to meet your goals.
Smart Coaching means results. The RS300X incorporates Polar's Smart Coaching software, which includes features such as Fitness Test, OwnZone, Smart Calories and Training Load. The Polar Fitness Test can measure fitness levels accurately in five minutes based on resting heart rate and personal data, and works with OwnZone to create optimal training zones to improve fitness. OwnZone guides users through a workout, indicating when to walk, jog, run and more.
Smart Calories uses the wearer's profile to accurately report calories burned during a workout. Training Load balances the need for rest and exercise by recommending when you should go all-out during your workout and which days are better spent relaxing. Owner reviews praise the Smart Coaching features, claiming positive results.
The RS300X can work with the Polar GPS module (*Est. $130) to track distance and speed. If users frequently run indoors, the Polar S1 foot pod (*Est. $50) attaches to shoelaces to track speed, distance and cadence. Interval timing allows the user to record lap times, and you can upload workout data to your PC or use the tools available at PolarPersonalTrainer.com to set up your training and monitor your progress. However, that requires the purchase of the Polar FlowLink module (*Est. $50).
Big features, small screen. Several users say the display of the Polar RS300X is too small and difficult to read. Others, particularly those new to heart-rate monitors, find its many features to be too much to handle. For novices, a basic heart-rate monitor like the Polar FT1 (*Est. $45) might be a better choice.
The RS300X's batteries and wristband aren't user-replaceable, and Polar advises owners to send the unit back to the manufacturer to change the battery, which lasts approximately two years. That's a source of some annoyance among owners.
Long warranty. Polar provides a lengthy two-year warranty with the RS300X, and relatively few users post complaints regarding customer service. However, reports regarding other Polar products are mixed. Some owners call customer service excellent and phenomenal, but others say it "leaves something to be desired."
Review Credibility: Very Good The RS300X gets feedback from more than 150 users posting at Amazon.com, where it gets an overall rating of 4.1 out of 5 stars. Most of the reviews are brief, but a few offer lengthier reports on the ownership experience.
Review: Polar RS300X Heart Rate Monitor Watch, Contributors to Amazon.com, As of March 2013
2. The New York Times
Review Credibility: Very Good Belopotosky writes a brief review of the Polar RS300X, focusing on its features compared to the Polar FT60. Her write-up includes a list of pros and cons. She recommends the RX300X SD for those who like the FT60 but want stopwatch and interval timing features.
Review: Marathon Tech Review: Watches, Danielle Belopotosky, Aug. 18, 2009
Review Credibility: Very Good BikeRadar.com gives the Polar RS300X 3.5 stars out of 5. Although the heart-rate functionality is top-notch, Cook says the display is hard to read while exercising and the separate GPS pod takes a long time to acquire a signal.
Review: Polar RS300X G1 Heart Rate Monitor Review, Nik Cook, Jan. 11, 2010
4. Runner's World
Review Credibility: Very Good Runner's World magazine recommends the Polar RS300X for exercisers who want a lot of heart-rate data. Testers say the chest strap is comfortable, but navigation can be confusing at first.
Review: Time Machines, Matthew Honan, Jan. 4, 2010
Review Credibility: Good Site editors recommend the RS300X, saying, "(It) can offer you all of the important training data you need to design a smarter training plan." Owners also post comments, and the unit earns 4 stars out of 5 from more than 15 reviews.
Review: Polar RS300X Running Computer Heart Rate Monitor, Editors and Contributors to HeartRateMonitorsUSA.com, June 2012
Review Credibility: Fair Site founder Squire reviews the RS300X and concludes, "A RS300X is an underrated powerhouse that is definitely expandable and gives you loads of data as well as options." However, testing isn't detailed.
Review: Polar RS300X GPS Watches, Rusty Squire, Not dated