I've been hammering away at my JBL for a few years now (although I recently also bought a Sony 300 on Ebay, which is also excellent - who needs Pearl or wifi?).
Considering how many 000's of times I've bashed the JBL's buttons and thrown it around in my gym-bag on the crummy old London buses, it has proved remarkably resilient. Perhaps the 'back' button is a little resistant now. The screen is 99% unscratched.
Not without its flaws and glitches, but one of the best gadgets I've ever bought, in my opinion. I was talking to a Kindle3 guy on the bus the other day... he told me that its screen froze after hardly a week - took it back to John Lewis for a replacement