I had CDMA in the past and the signal wasn't as good as what I have now GSM plus no roll over. Now thats in my area and that's the key, the area your in. Having said that I wish every carrier sold the iphone. It would only bring down the cost to the consumers. That's why I say the iphone will stay with at&t because they (apple & at&t) can control the price which is not good for the consumer. Apple gets to keep it's premium price for the iphone and at&t can keep it's monthly rates high. As long as there is a huge demand for the iphone it will stay with one carrier. You know, when there's more than one retailer selling the same product you can haggle over the price.
I have had better luck, signal wise, with CDMA networks. That being said, im sure its about location.
I agree with the other things you wrote, however i don't want to see the government force Apple's hand in bringing the iPhone to competitors.