You got Spotify to stream over LTE? I tried it and the watch immediately goes into overheat mode... like immediately. Googled and saw other people had the same issue. I assumed it was a bug in the app.
Not sure if this was a fluke, or something was fixed. I've tried streaming Spotify over LTE since then and it worked fine. Last night in the gym, I got bored with my downloaded playlists, and went to browse, tried several different choices of recommended playlists and genres and they all worked fine.
I am still loving the experience with the Gear 3. What I have found is that sometimes it doesn't reconnect to my Note 8 for some reason so the battery runs down more quickly being in standalone mode with LTE. I need to play with this a little more to see if I'm doing something to cause it not to reconnect when I go to the gym, etc..