Airbrushes

Despite the poor economy that I keep hearing about, I received a bit of a raise this year. So, to celebrate, I'm looking into buying an airbrush. As is becoming typical for me, I'm doing some research on whether it's worth getting, what to get, and what I can expect in terms of learning curve. Mostly I've been trolling around BrushThralls, CMON and the Privateer forums for information as those are places that I routinely haunt and find useful information on. Below I'll put a list of links, but first is the summary of my research and my current plan.

History:
I should mention, I've actually had a small amount of experience with an airbrush before. Nothing really valuable except to have an idea what I'm getting into. Long ago (back in college) I bought a Testors airbrush kit. I think it was about $50 and included a single action, external mix, siphon fed airbrush that used compressed air cans for propellant. It was a pretty feeble tool and not especially good for models, but it did give me some experience with what an airbrush is all about. I used it back then a couple of times for basecoating 40k stuff and doing some random things to larger vehicle models from that 40k line. That being said, if I'm going to try out airbrushing again, it's time to upgrade to an adult version.

Requirements:
Yes, yes... my developer side is showing through. My first step was to determine my requirements for an airbrush.
* Double Action - Absolutely necessary. I want the added control of how much paint is coming out.
* Internal Mix - External mixing is just too random. I want control. If I've learned anything from the W&N S7 brushes it's that tool quality and consistency does make a noticable difference.
* Separate Compressor - No compressed air cans. I'll splurge for the compressor even if it costs me. This gets back to that whole tool quality and consistency issue. The compressor must have a pressure regulator (variable) and moisture filter. Ideally it has a tank option as well.
* Budget - My working budget here is about $250. I'm not really willing to go more for now, but am also working under the assumption that if I really like it, I may get another airbrush further down the road (although hopefully not replacing the compressor).

Candidates:
Right now I have 2 leading candidates. First is the Paasche VL Millennium which has the advantages of being relatively cheap and entirely metal. Second is the Aztek 470 which seems to get a lot of recommendations. I'm not in any immediate rush to get one, so I'm going to take my time and ask around at a local hobby store and get further recommendations.

Links:
* BrushThralls has an excellent brief article about airbrushing that gets right to the point and, most importantly, includes a couple examples of actually using the airbrush on models. Yay ArkenTyre!
* CMON Has a good article about Airbrushing basics that I found very useful.
* Not to advertise, but DickBlick's airbrush section was useful to get an idea of accessories for further down the road.
* Privateer forums had a couple of posts that I found informative about selecting airbrushes and compressors.
* How To Airbrush.com - An interesting site, I guess, but there are so many spelling and grammar mistakes that it is rather hard to sort through the information.