Thanks for your help guys. I understand that the Fenix can't be used for GPSTC but I will use it for results on the water while GT31 is used for the download. Might download the Fenix to KA72 just to compare.

I downloaded the data field, it looks good. It looks like the only thing missing is the nautical mile??

I'm part of a runners group and I'm amazed how marketing has managed to excuse some shortcomings while hailing the power of the "algorithm". Your watch is great and you are happy about it, perfect. I'm not here to convince anyone otherwise. Sensors are great provided you buy them on top of it. Vendor lock-in is great too, especially for current Suunto users.

Still, in light of what I read above,I'd like to quickly point that Fenix 5X Plus is 51x51x19, Motion is 66x54x16, display is bigger, battery-life is longer, overall accuracy is better, update rate is higher, price is halved. I'll concede it lacks a barometer and sexiness. If anyone lacks something software-wise, I'll add it. It *is* used in other sports. I'm currently adding very low frequency computations for very long trails. I've just removed some constraints for a very fast car.

It's good that we have different options and it's good for these options not to all look alike.

Just a note to watches for other sports and the Motion: for swimming, especially indoors, it's all in the algorithms. Calculating distance and speed from accelerometer data is extremely prone to errors, so if a watch tells you that you swam exactly 2000 meters, it has been using information about typical pool lengths to come up with that number. Not rocket science but works well. For triathlon swimming use (probably a market that's at least 100x bigger than windsurfing), accuracy really just depends on two or three points (end points plus middle if it's an out-and-back swim). Worst case is about a 10 m error - less than 1% in a 1500 m swim. Typical accuracy for a regular-length marathon should be closer to 3 m / 1500 m, or 0.2%. Definitely good enough for any purpose except actually scoring triathlons.

The Motion is very different from Locosys units, and in some respects closer to watches like the Fenix or Suunto. The Motion uses one of the best GPS chips in existence - about 2 decades newer than what's in the GT31. Unlike the Locosys units, it has a lot of computing power on the inside. That means it can easily calculate nautical mile and 1 hour averages. It also means building apps for other sports is entirely possible. We got lucky because Julien is a windsurfer, and made the Motion for windsurfing. Any "market based" approach would give windsurfing resources proportional to the relative market size - perhaps a couple of hours a year. I can think of at least two similar GPS developments that initially had a windsurfing connection which later disappeared because other markets were so much bigger.

Yes, they bought it as a customized big font display without cables they can re-position or remove at will. They do have ECU real-time peeks and logs for engineers.