While this isn't going to prevent determined hackers or law enforcement, it is great to just hide away your personal files from prying eyes.
It's easy to use, and while 8GB is a little small these days, it's great for documents and such which would be the intended use anyway.
I found mine without a master key set, so it was pretty trivial to format it and set a new pin for myself, which is pretty good because it reduces the desire to try and hack the security.
It's very user-friendly, though it does take a quick read through the manual to fully understand the combinations of LEDs and the timings.
The keypad is nice to use, though I do find it a little unsettling when it comes to wanting to use the same number twice, because you're not sure if you're getting the 2nd digit of the button or a 2nd occurrence of the first number of a button, it's not clear how long you must wait before pressing the key to get a 2nd occurrence of the first number.
I do like that it's an os independent (filesystem withstanding) security system, as most "security keys" are just normal usb keys with cheap propriety software bundled, which is worse than just using truecrypt portable with a cheap normal usb key.
I'd recommend it if you just want to prevent snoopers, the only people that will get around this are determined people via smart memory-dump hacks, or battery-disabling brute force attacks. So very determined hackers, high budget competitor corporations, law enforcement.
If you want extra security, you can always put truecrypt portable on this as well, and setup an encrypted file to hold really sensitive data.