Clearly you know about large roaming fees. Yet you don't seem to be willing to sidestep the issue by leaving the phone at home. That just means that you are a troll.
My CDMA phone had a very important quality that a GSM phone does not: If I forget to leave it at home, flip some switch, do a little happy dance, or whatever it is I'm supposed to do, it won't ruin my life.
Ever heard of risk management? If a house had a big, red button one had to press once a day to keep it from exploding, I could "sidestep the issue" by just remembering to press the button, but there's no way in hell I'm going to buy such a house. I have more than enough things in my life that require my vigilance--I don't need another.
Thank you for the rest of your informative post. I already go completely pre-paid, partly for the reasons above, and partly because I want to be able to switch carriers rapidly when they (inevitably) screw things up. So far I hadn't found anything authoritative that says that a pre-paid SIM even works in an Android phone. (Well, I guess I still haven't, but at least it's another data point.)
The first phone company that comes out with a simple deal that says "this is what you get, this is what it costs, cancel anytime" is going to wipe the floor with the rest of the competition.