I'm not sure if I am remembering this correctly, but out of th bottle Red Line oil is an amber/red tinge. Same with MTL. ATF is red(duh). Gear oil is just amber.
After use, I think depends on the car. My car it is extremely dark very quickly. Probably partly from blow-by and I think my engine may still be a little dirty though too.
In the '01 GTP, it still looks almost like new after over 3k miles so far.
All oils turn dark, so I'm not sure what you meant by "dark like conventional oils". I guess if there was no blow-by or contaminants, conventional oil would darken before synthetic from oxidation, but that'd probably take a while.