C1Rebel has some troubles with red/purple colors using its 300D profile, but there is some workarounds to it. Here is the comparison between the standard Canon RAW conversion libraries (in this case, called from BreezeBrowser), and C1Rebel using its 300D profile, using a "borrowed" 10D profile from C1LE and a +7% of color saturation, and the ETC 300D profile. All programs using default parameters, and keeping the shooting parameters except colorspace. It was changed to sRGB in all cases to match Web output.
All conversions done to 8-bit TIFF. Rescaled to 1/3 and saved as JPEG Quality 10 in PS. No other modifications done.
The "reference" shot (BreezeBrowser using Canon libraries):
C1Rebel + C1Rebel 300D profile:
C1Rebel + C1LE 10D profile:
C1Rebel + ETC 300DHiSat profile:
UPDATE!! This is an old comparison done using the C1Rebel V1.0. The V1.3 300D profile is in fact similar to the 10D one used in C1LE, so the "purple color" problem is gone, but you must increase the saturation as in the 10D trick. Also the new ETC 300D profiles solved the "flat shadow" problem present in the V1.0 one. I noticed the new version renders a more contrasted image with more saturated colors using the ETC profile also
This is the same image processed with C1Rebel V1.3 + ETC 300D HiSat Profile V1.3:
Well, that's all. Enjoy