Yeah I had heard that about the Fenix 5 which is why I went with the 935. I am finding that even compared to my Garmin 530, the 935 has much better tracks than anything else. The 530 is pretty bad with GPS plotting as well. Also hearing the 945 may be worse than the 935 so staying put for now.
What I see in the native Apple workouts map plots is major smoothing of corners, cutting through things at the curves (houses, bodies of water, etc). vs following the track. The Garmin at least follows a track. The AW just seems to want to render nice swoopy lines.