I love a good split keyboard discussion. I agree with Input Nirvana about the reassessing the value of your keyboard based on daily use. When I am working and at home, I will be using the keyboard every day. It makes sense that I will make a good investment into the keyboard. I take this same attitude towards most things that I use everyday.
A year ago I was in the same boat as you. So in the past year, I have bought a Goldtouch, Kinesis Freestyle, Maltron and Kinesis Advantage. The great thing about ergonomic keyboards in the resale value. I was able to sell the Goldtouch and Freestyle for nearly as much as the purchase price. Plus, Kinesis does have a flexible return. Getting your hands on a Maltron for cheap, however, is a different story.
The Kinesis Freestyle does have a better key feel than most rubber dome keyboards. But when I used it next to keyboards with mechanical switches, I could feel the difference. And that modified right shift key on the Freestyle was the bane of my ownership.
Surprised that nobody has mentioned the uTron yet in this thread. I'll be the first. Although it has an abnormal layout and costs a boatload to ship from Japan. Might be way out of your price range. Here is a picture from webwit's keyboard parade on deskthority:
http://webwit.nl/input/utron/utron7.jpg.
The Kinesis Freestyle with Cherry Switches does sound intriguing. I would like to see that. Somebody has mentioned the Ergodox. Can't wait for that to come to fruition.
My personal fave at the moment is the Kinesis Advantage. Did not take that long for me to learn the layout, the depressed key wells really reduce hand and finger movement, which is a huge plus and increases typing speed and decreases mistakes. I'm even typing with the Linear Feel and my mistakes are lower than any standard rubber dome that I have used over the years.
Also, Maltron, whose ergonomic design I prefer over any other keyboard, claims to be releasing a programmable model in the near future. Now, if they could make a split version of their design...
What an exciting time in the world of ergonomic keyboards!