Coming from a stainless steel series 7. You definitely feel the weight, but it’s not uncomfortable in any way. I’m testing everything as you do. I slept with it on to test the sleep tracking. I’m curious to test the battery claims. I took it off a full charge at 7:50 last night and now at 7:15am it’s at 85%. That includes a 20 minute walk I did this morning. AOD and raise to wake are both off.
Got mine 2 days ago and I love it - update from an S6. I haven’t found the size or weight to be an issue at all. Using the WorkOutDoors app on it is great with the larger display. And battery life seems really good.