I switched my G3 also for the Note 4. Luckily I was within the 14 exchange window with at&t when the Note 4 came out. I gotta tell you I really really liked the clean look of the G3 (with out the tiny lag once in a while and the heating up when playing games), So I changed my Note 4 to look the same. Could't be happier!
I will sell my G3 once my Note 4 arrives. It arrives today. Lol. I loved the g3. Mine did not overheat but does lag and the constant re-draws of the app draw and home screen do get old. But other than that the G3 was perfect. I very much look forward to returning to the note series though.