I've had this a couple of weeks but had other distractions. I finally got around to transforming it and it's very impressing. The robot mode has a definite presence about him.
I was having troubles with the back pack. I found most reviewers mistransformed this figure (including Emgo). They don't slide it up all the way. On the sides you shouldn't be able to see the white grill at the bottom. It took me about 4 or 5 videos to find someone who did it right and could show me that I was doing it right, but I just needed some more force. You keep the halves separate, slide the base all the way up and then when you squeeze the halves together there's a solid click on each side.
For anyone interested, check out the video review from "TMReviews".