"Sprint should be getting the iPhone by mid october "
Really? You're basing your choices on an unconfirmed report, a rumor? The iPhone is expected to appear, but nobody can confirm what it will do or whether it will be reliable. I remember friends of mine with LG Voyagers all hot to get the EnV Touch - which looked cooler and was (on paper) a cooler phone. But it was incredibly unreliable. People had no way of knowing that until after the phone had been purchased by and proved a heartbraker to the early-adopters.
"now I have an evo 4G"
Is it a 4G phone, or is "4G" just a name? Because if you want to rely on rumor, much of it surrounding the iPhone seems to confirm that the iPhone 5 will be a 3G phone.