I've used a couple, and I find them totally underwhelming and bloody hard to hold and use at the same time. They're fuckin' huge and have a horrible frictionless back, which means you'll spend more time catching it as it slips out of your grasp than using it.

If you want the same functionality, save money and get a 32gb iPod Touch and keep your current phone (heck, you could upgrade it to something really snazzy and still pay less altogether than an iPhone).

So from me it's a bad review - I wouldn't recommend it to my worst enemy.