That was probably my favorite scene from Age of Extinction. I just love how excited Hound is when Optimus is coming back. Gave me chills both times I've seen it, such a well-done scene. I just wish that one or two of the old favorites from the other movies were there too (maybe even in place of one of the new guys). I'd have loved to see Sideswipe there too at least. I feel like it would've had even more meaning if someone we were familiar with along with Bumblebee was there too to greet Optimus.