I've had a few troubles with my Preview Pack Optimus.
First, his left hand broke. I didn't put anything in his hand other than the pack-in rifles. It wasn't too much of a problem, figured it was just a fluke and decided I would get some crazy glue later on. Then I looked at his other hand, and sure enough there were stress marks, this time on both his thumb and fingers.
Today I was playing around with him and Cyberverse Sentinel, getting them into some dramatic poses. I took off Optimus's jetpack and found a piece of a C-joint had broken off, the one that holds the jets in truck mode. It still holds, but it's very loose.

Has anyone else experienced this, or was I just unlucky? I'm loving Cyberverse so far, Sentinel is practically a mini leader class and the packaging is awesomely collector-friendly, but I'm not gonna be buying crazy glue every time I get a figure.

 

I find those joints to be weak no matter what line they are in. PCC Mudslinger had terrible joints.

 

Hm. Guess I might limit myself to deluxes and the odd voyager. I really don't want to deal with broken hands.

 

No problems with mine so far. He's held together surprisingly well, for his size class.

 

Wait. Scratch that... stress mark on the right hands thumb. Stress mark on the left hand fingers.
Beware.

 

Makes me even more glad I passed on the ones I saw last night. Maybe the half open hand idea was just not quite as good as it seemed on paper.