I've got no complaints, really. My 350 regularly sits in my work gear bag full of all sorts of nasty little things that can cause damage to sensitive technology. I've got a 350 in there with the sony cover and the soft case.
In all the time my sony has been there moved, thrown, dropped, dumped from one bag to another, I haven't as much as even scratched the damn thing. But I did break two pairs of unibody military grade oakley sunglasses.
I even dropped the 350 when it didn't have a cover from about 4 feet onto ceramic tile. Like the day I got it...I about crapped my pants, but picked the sony up with no more damage than a barely noticable nick on the finish.
Matter of fact, the only damage I ever caused was when my first 505 broke. It fell off a table and landed right on the little metal frame, breaking the spring in the power button. That only made it difficult to turn on because I had to push the switch a little harder. And the frame loosened. That lasted until I forgot to charge it for like two months straight and the eInk display died. But, that was a 1st gen eInk. Tech's improved since then..i hope
Matter of fact, my 350 has also sat in the same bag as my Macbook Pro. And while my Macbook makes a creaking noise on the hinges every now and then and there's also sorts of dimples on the face of the laptop aluminum, there's been no problems with my 350..
And every time I take it out I'm crossing my fingers hoping for no damage. I've been lucky so far