I've owned cell phones for over 20 years. I've changed phones regularly every year or so always looking for the best one. I've had other Smart phones but bought an iphone when they first came out and I'm now on my second one - passing the first one to my wife. My two sons have the 3rd generation iphone, also having bought the first generation phone when they first came out.
I've looked at others just for comparison and they all come up lacking. I'm hooked on the iphone.
I know a total of 5 paramedics who I work with who have all made the jump from their blackberries to the iPhone and all of them absolutely love it. Most of out doctors here also use it.
I took mine in France a year ago and it was the most AMAZING thing I could have done. Had excellent service(better than a lot of local carriers), and never had problems with it.
It is a pricey little machine but you get what you pay for. I would highly recommend the iPhone to anyone.