Been using Polar HR monitors since the early 90's so I'm a big fan and overall the RS300X is impressive, although I do have two gripes.
The start/stop button doesn't always register when pressed - I've had dozens of runs where I hit the start button, only to get a mile or two into the run and realize it hadn't started the chronograph...."
Mercent.com by JRoc6673, Apr 27, 2012
Excellent, but i had to specify UPS.
I would recommend the same because of the value of the product...."
Mercent.com by aeronca, Nov 14, 2009
great watch/ better than the suunto
"...first off, this watch is the direct cross for the suunto t3c, but better. i went through three suunto's before i had enough and took the last one back.
the rs300x works the same way, the functions are almost the same, just displayed a little different, and the polar,so far, is completely reliable.
the chest strap on the suunto was designed by an idiot,while the strap for the polar is actually well thought out and wont continually break...."
Mercent.com by TheOso, Apr 9, 2010
The right watch for a man.
"...I have started training for a half marathon.
I am extremely pleased about how accurate the heart rate monitor and calories burned are.
The waist band is comfortable and large enough for a big boy...."
Mercent.com by Numbersguy, Sep 28, 2011
Top Notch-Little Fluf
"...I like a dependable/reliable product that gives me what I need without a lot of "extras".
The RS300X is that type of product.
The chest band is very sensitive; following Polar's recomendations to wash in a washing machine at least after every 5 uses is a must, otherwise readings on the monitor will be off the charts...."
Rei.com by Randyman99, Apr 11, 2013
feature packed, but takes time to learn
Let me give some background of previous HRMs I've had and my likes and dislikes to put the Polar RX300 in perspective.
Over 10 years ago I had a Polar Protrainer NV...."
Rei.com by Ray52, Mar 10, 2013
Nice feature, easy to use
Make sure you wet the contacts on the chest band before putting on.
Rei.com by OOToole, May 21, 2013
Good Beginner HR watch
"...However, the button placement is not very good. I wear gloves when riding and EVERY time I ride the buttons get pushed by my gloves.
This changes the screen display and even starts / stops my HR monitoring.
Rei.com by andrewmm, Feb 28, 2013
Dissapointed at lack of basic function
I'm a runner and wanted to push my training to the next level by tracking my heart rate.
I'm your slightly better than average weekend warrior runner...."
Rei.com by Biker Meg, May 2, 2013
"...In theory, this should've been a great HRM.
Polar certainly has a good name in the business.
The first thing I discovered when I opened the box was that the battery in the transmitter was dead...."