I do not use the recovery metrics on my Garmin 945 (and former 735XT), but I do look at them after every activity. They look reasonable and aligned with my level of effort on a workout and when I would be back to strength. I would trust the directional accuracy and usefulness if you wanted to structure training around them. There probably have been a few times when I did a very hard workout, saw a multi-day recovery, and skipped that next workout because I was still tired.