I personally never had Sprint but I've had US Cell, Verizon, and now currently AT&T.
I currently have AT&T and the old iPhone and it's the best phone out right now by a long shot. The web browsing, iPod, text messageing, visual voicemail, google maps features are amazing. Not to mention how easy it is to use any of those.
With the new iPhone 3G, it has all of the above PLUS GPS and a new exchange server but that cost extra if u need to use it.
Why are people even complaining about the price? THE PHONE IS $199. I bought mine at $399 and thought it was a steal cuz it's the best electronic device I've ever bought. I know the data is more expensive and blah blah.
Breakdown:
Old iPhone - 399(phone) + 480 (data)(20x24) = $ 879
New Iphone - 199(phone) + 720 (data)(30x24) = $ 919
New iPhone - 199(phone) + 840 (data)(35x24) = $ 1039
+ 200 texts (text)
If you get the new iPhone 3G without the text, you are only paying $40 dollars more!! If you buy it with the text, you are paying 160 more but that's only $6.66 a month more for the 2 years.
People make such a big deal about the 3G service but since the phone is WI-FI, there isnt' areas where you don't have WI-FI. Also AT&T has easily the best data coverage in the US. Sprint has the EVDL but that's like 3G, it's not everywhere. Verizon's data coverage is not very good also cuz they use different towers for their voice and data. When I was with Verizon, I would be traveling and not get any text messages but all of a sudden I get like 5. I found out that it's because I was not in near a data tower and once I made it to one, it sent me all the texts.
One main concern that I had before I bought the iPhone, is the typing. Since it's all touchscreen, I have bigger fingers and thought I would misspell alot of words. That's where the auto-correction program amazed me. Not only does it autocorrect, it recognizes the words that you use alot that aren't in the dictionary that you want to type if you typed those words a few times previously.
To answer the question of IS IT WORTH IT? My answer is simple, YES. NOTHING and I mean NOTHING is even close to the iPhone right now.