Discount Polar CS300 Cycling Computer and Heart Rate Monitor

I bought this used for about 1/4 of list price. The reviews weren't that great but given the price it was worth a gamble.

The good:

- easy to set up
- nice array of features
- has worked great so far aside from the alarms and sonicLink (now fixed)


The bad:

- alarms were inaudible when I first got it
- sonicLink (due to low volume) wouldn't initially work
- not Mac compatible
- speed sensor has to be placed high on fork to minimize interference
- instructions had wrong setting listed for my tire size
- batteries in watch and speed sensor aren't user replaceable*
- you can upload data form the CS300 to the polar website but you can't
easily move it anyplace else.

Given the longer list of "bad" things you might be surprised that I rated it as high as I did. It turns out that all the important items in the "bad" list I was eventually able to address or work around. For example, like me, another reviewer complained about the sounds from the watch being inaudible and he had that problem with 3 separate CS300s that Polar sent him. This is a big deal because the CS300 uses sounds (like a modem) to transmit saved information about your exercise sessions to the polar personal trainer website. There's no other way to get the data off the watch.

In my case the CS300 was a couple years old when I got it and since I'm not the original owner, -no warranty. I replaced the battery on my own hoping that would fix the sound problem. Now, you're supposed to send it to an approved Polar Service Center to change the battery to ensure that the unit retains its water resistance. I may eventually have it pressure tested by a local watch repair shop but I wasn't inclined to spend the money sending it to Michigan just to see if changing the battery fixed the problem. Anyway, the first battery change didn't do squat. The only reason I thought it still might be the battery is because the backlight was a little on the dim side as well. Going for broke, I tried a different battery, and ...SUCCESS

One of the big reasons I wanted to do this review is that given some of the other reviews, I was surprised at how well the CS300 worked. I use my bike to get to my job and a part of my ride is next to a Light Rail line. It uses overhead lines to supply its power and this is one of the things that can cause interference issues between the speed sensor and the CS300. I've had no trouble whatsoever. That may be because I mounted the speed sensor as close to the CS300 as I could. Other people have complained about the speed and distance not being accurately recorded but this may because of the improper numbers listed for at least some tires sizes in the manual. Once I had that set properly, the reported distance and speeds matched my wired computer.

I have to say that even though I did get the sonicLink data transfer to work, it took some trial and error. It's the type of thing that may work great on some people's computers and not at all on others. My recommendation is that if uploading the data to the Polar website is an important feature to you, get the CS300 from somewhere that has an easy return policy.

For me to give this thing 5 stars it would have to have true Mac compatibility, a better method of transferring data than SonicLink, user replaceable batteries in all components, and more resistance to interference giving you greater flexibility in sensor mounting.Get more detail about Polar CS300 Cycling Computer and Heart Rate Monitor.