A good and fair review of the Apple Watch Series 3, from the point of view of athletic training and fitness vs. other sports watches and smartwatches:
https://www.dcrainmaker.com/2017/11/apple-watch-series3-cellular-fitness-sport-review.html
(To go right to the Summary...)
https://www.dcrainmaker.com/2017/11/apple-watch-series3-cellular-fitness-sport-review.html
(To go right to the Summary...)