Rating: - Great for the average runner (like me !)
I am very happy with this watch. I really enjoy running and I wanted to learn how to get the best benefit from running without over-exertion and injury. The polar website said heart-rate monitoring helps with pace, getting the desired benefits from my run, and helped to reduce injury.
Rating: - It meets my expectations
The S120 meets my expectations, I use it alot at the gym & riding my Mountain Bike. I recommend if you are a person who is looking to keep track of the info from this monitor, the S150 and a few other models has an attachment which you can plug into your computer. Also the S150 has a mount for your bike and alot more useful options. All in all I am happy with the S120 it is simple to use and I have no complaints.
Rating: - Watch is fine, but manual is a little confusing
I had a Nordic Track heart rate monitor watch before this one and it was very easy to use. I recently broke it...changing the battery, so if the manual says have an expert change the battery *sheepish grin* it is better to listen. I was looking to buy a comparable watch with maybe a few more if not similar features. This Polar watch has so many functions it was a little daunting at first. The manual is confusing and it took me an hour (maybe longer) to set the watch exactly as I wanted it. So far the watch has worked fine for my running and aeorobic routines. I really like the quick transmitter review of min and max heart rate as well as TIZ without having to push a button. I would recommend it to those who do not mind putting in the time understanding the manual and one who needs all the different functions.