The F104 is a good car, but slow against the 103 and 109 cars. It'll take a few more versions of the 104 to get up to the speed and handeling of the 103. I'm planing on retiring my 103, even though I've only ran it this season. Once it's over, I'll be spending quality time with my 104 next season, and I'll get thrashed even worse than I am now. But at least I'll be enjoying it.
As far as that corally F1 goes. I have no idea, it's a rare car on the track. And I'd imagine it's expensive, both as a kit and to up keep.