I would go with whichever feels the best in your hand (controls, dials, etc.) You didn't say which Canon film body you currently use, but if it is a 1V or 1Vhs a 1D is basically the digital version (all the controls are in the same location on the camera.) I shot for over 2 years with my EOS 1Vhs and when I picked up my 1Ds I felt right at home. I've shot with both the D1x and the 1D as well, and in my opinion the 1D is a more accurate and versatile camera (AF is 45 points vs. 5, plus awsome auto white balance.) The one feature I like best on the Canons, are the custom tone curves. I've set up 3 or 4 to match my favorite films (Astia, Provia, etc.)
On jobs, I ALWAYS shoot RAW, It takes longer to process, but the increased post shot adjustment capabilities (and piece of mind, +/- 3 exposure compensation =) ) are worth the time. I always use Captue One DSLR or Adobe's RAW plug-in for any adustments.
Also, so you know the 1D will not be discontinued any time soon. It has quite a bit quicker continuous shooting than the 1Ds (it is aimed at sports photogs, 8fps in bursts up to 21 vs. 3fps in bursts up to 10 on the 1Ds.) It can also be found below the manufacturer required (MAP) Minimum Advertised Price right now. About $3,500 if you do some price searching [img]/ubbthreads/images/graemlins/smile.gif[/img].
Let me know if you have any other ?s, and keep me posted on whichever you decide.
-Jason
Michell Taylor shot with 1Ds