I have seen the video and the flexing was hard to make out... but I am willing to bet that any kind of flexing is bad.

also, I notice some of the movement you see is from the engine itself?
is that amount of movement normal? what rpm were you revving to?

sure looks scary from that angle...

 

How about using Imagestation.com or someplace like it?
www.imagestation.com

2003.5 Garnet Fire 5AT

 

After just watching mine what it does it at idle it is flexed and then when throttle is given it goes back to it's natural shape. I could barely tell that mine was even "breathing" at all and some of the movement I saw was from the engine moving in it's mounts(I think I want a torque damper). This one is definatly stronger than any of the previous ones and it also flexes less as well without the use of the middle bolts. Also to those that have already gotten a V4 and looked at it can you tell me if your's had an rectangular indention in front of the center post about 2-3 cm wide and 1.5 cm long, it was a couple inches away from the front of the plenum and just wanted to make sure that it is present in other's as well.

Best ET: 14.730 @ 96.14mph(stock)
2003 Black 5AT sedan