If you never intend to post to GPSTC then a sport watch is great and if purchased locally covered by Australian consumer law.
Have seen this for GW60.

If you look look at Seabreeze there is endless issues with GW60 watch, buttons fail, buttons not water proof, band breaks, battery fails after about 150-200 uses, battery only lasts 5 hours on water, contacts rust, contacts require cleaning regularly, connection clamp pins stick, com port error issues uploading and long down time replacing when it fails.
Also only has GPS so misses data in SEQ and Northern parts of NSW.
KA stores all your data and can be filtered per location , date and 2 sec speeds. Also keeps total data per location for number of times sailed and total distance.

Upload the windsurfing App.