Mobile Phone Comapnies and the Man

This is an open letter to the mobile phone carriers and handset makers.

I am your target market, I have shit loads of disposable income that I'm not afraid to spend (as evidenced here) I'm an early adopter, I'm pretty sure I was one of the first to pay full on for hotspot access and the mobile web, I'll also go out of my way and pay for things that I can't get in the US and I'll even write up instructions to help people out who want the tech but can't figure it out. You want to help me out, really you do. So this is my current dilemma and the problem that you could solve by doing a couple of press releases and five web pages.
My K750i is on it's last leg. Which I had to go out of band to acquire. It wasn't problem free, the joystick sucked the phone was kind of slow and pretty much fell apart, but all in all it was a great phone and had a lot of cool features and I enjoyed it a lot.
As such I am the market for a new phone. Three of them are appealing to me. They are all Sony Ericssons the k810i the K800 or K790. They all aren't cheap but I'm willing to spend for it if I knew what the fuck to do.
I live in DC and I use T-Mobile and here are my issues with which one to buy.
The w810 and k790 support EDGE.
The k800 supports UTMS.
This is the first problem, I haven't a clue as to what the hell networks exists in my area and what the future plan is. If I get an EDGE phone now will I regret it in six months? Does UTMS exist where I am? Do I even need the EDGE stepping stone?
If UTMS is supported than the k800 is the way to go, it has the front camera and I can actually buy it now.
If only EDGE is supported on T-Mobile then there is another problem the first is that w810 is actually out and according to the SonyEricsson website says the K790 is out, but you can't find it anywhere. The w810 has the advantage of using the same memory that I have for my PSP (again with the disposable income) and what is currently in my k750i so I'd have a 2GB card off the bat. But the camera doesn't have nearly the same amount of features or resolution as the not to be found k790. So do I wait in the hope that I can find a k790 in near future or get the w810 and be done with it reusing memory and having it now. Or is the k800 the way to go, the fuck if I know because none of the companies give me a way to buy what I want or an idea of where it is going to go.