I'm changing my review after a couple of months of use. I have been running for nine months, this is my first running watch. I think that they are suitable for beginners, running with a watch is much more comfortable than with a fitness bracelet or just with an application on your phone. The watch collects a bunch of various statistics that help you train more efficiently. But glitches are constantly frustrating - either with the pace of trouble, or with the heart rate, in the end you just stop trusting the clock. Every time you think - did they intend to do it normally today or again show random numbers? They fail to do their main job. Not recommended for serious workouts.