I realize this has been discussed before, but it's a moving target and a discussion from months ago probably holds no validity today.
So I'm going to be out of the country later this year, and this time I really would prefer to have the use of my phone while I'm away. In particular, I'd like the use of data services, and free Wifi is pretty much not going to be available. Furthermore, I'd like to use such services without feeling like a giant Dyson had its hose stuck into my bank account, continuously demonstrating how it never loses suction.

The only solution to all of that would be to unlock my phone and buy a local SIM card to use for the duration of my trip. On any other phone, that would be a no brainer. But apparently AT&T is unwilling to unlock iPhones, even after your commitment to them is satisfied (does anyone have any evidence to the contrary?)
So I took a fresh look at unlocking solutions, and from what I can see, the options are limited. I'm fully upgraded to the latest firmware (4.3.5) and baseband, which limits what I can do. Apparently (a) you can't unlock without jail breaking, which is a shame (I'd rather not jailbreak if I can avoid it, because I hear there are big issues with battery life and perhaps other things once you do so.) And with 4.3.5, the only jailbreak is a "tethered jailbreak" which means you have to connect the phone to a computer and go through a series of steps every time you restart the phone, otherwise it will be a brick. That's not an option, particularly when I'm going to be traveling and obviously turning off the phone on the plane.
There are sites like this advertised:
http://www.iphoneunlocksim.com/ but they provide so little detail that I'm skeptical that it isn't either a scam, or that there aren't big limitations that you won't discover until after you've screwed up your phone.
There's also a hardware-software solution involving a little device that sits in between the microSIM card and its interface, but that, too, requires jail breaking the phone which introduces all of the tethering issues.
SO... my question: does anyone know of a practical way to make this work? Or should I just plan to live without phone and data services while I don't have a WiFi connection? It's truly infuriating to me that AT&T won't allow you to unlock the phone. When I used to have T-Mobile (pre-iPhone) they were great about allowing me to unlock my phones, even before my commitment was completed, just based on my good payment history and credit. AT&T (and Verizon too, I guess) failing to do so seems borderline criminal.
This is an issue that would definitely get me to switch to another carrier if there was one with a more reasonable unlocking policy. Are you listening, T-Mobile?