Be careful with these things. I didn't think the new PW's were too frail until last weekend. I had a 580EXII mounted on the Flex's hot shoe and both were sitting on a bed while I was testing out the settings I just updated the Flex with. As soon as I got the settings straight the units took a tumble onto carpeted floor from about 18" and separated. The 580 took the hot shoe with it. Tiny screws hold the hot shoe in place and I was able to get the hot shoe back on but the Flex no longer triggers the flash from the hot shoe. It's receiving the signal but won't trigger the flash. 
Totally my fault and I know it's designed like that to prevent a more expensive repair to the flash but from only 18" onto carpeted floor? The tolerance for impacts is just a little bit low IMHO. Now I feel like I have to baby these things.
Called up MAC and they told me it was a $40 fix (+ $15 to return ship) so I sent it in. PITA.



