It's true that Vaios aren't ThinkPads, but provided you treat them right they aren't 'fragile' either.
Poor support? For software, sure. As for hardware? I don't know, I've never had a problem that bad yet (except for their stuck-pixel policy. There's a tiny red stuck pixel on the display, and they have a "minimum of 3" policy going on there... (I might try to get them to fix it when my warranty is about to expire in 2013 though).
Design flaws? I haven't noticed anything 'flawed' about any of the Vaios I've used (in 2005, a purple one dating back to 1999 running Windows ME. A 2006 Vaio which I forget, a 2006 Vaio FE (still chugging along as my parent's HTPC), and my Vaio Z. A friend of mine has a 12" Vaio that's a couple of years old, only problem is the power button fell out).
My only other suggestion is to get a MacBook Pro then.
@blowdart: Interesting, I have a Sony VAIO Z and it's my first Sony laptop. Absolutely love it, it's everything that I want in a laptop - light, fast, SSD, good battery life, built-in DVD drive and SSD drive.
I haven't really had problems with it, although my HDMI output may not be currently functioning
HDMI only works when you've got the NVidia card selected. BTW, the Vaio Z doesn't come with a DVD option, it's either nothing (where you get a 2.5" mechanical HDD in optical bay) or a Blu-Ray drive (with SSDs crammed in under the palm-rest. Which makes that option obscenely expensive).