Some time ago I had a couple of conversations with the people at RTI and also a separate convo with Stan Rick about colored vinyl.
As far as the "picture discs" go, I regret that I cannot recall the specifics, but they are [relatively] crap.
Now, as far as colored vinyl goes, there are different combinations with slightly different *potential* sonic issues. For today's (and almost all past) LPs, there is some carbon black which is part of the mix, and compared to vinyl which uses only dye to attain its black or near-black appearance--like the JVC Supervinyl--there is apparently a very slightly higher degree of noise. Slightly more noise can come from albums which use a type of oxide (I *think* its titanium dioxide, but I'm not sure -- in any event it's a commonly used whitening substance in various industries, if that's not the correct compound) as the whitener. This would be used for all-white vinyl LPs of course, but is also used when you want to have opaque colors rather than 'clear' colors. If you just use red or purple or whatever dye, you will have a [somewhat] clear red, clear purple, clear whatever LP. Adding some whitening agent makes it look flat/opaque, kind of like you would think of a crayon color.
So anyway, the dye-only LPs (like JVC) are quietest, followed by regular black LPs (from the carbon black) and then by LPs using the whitening stuff (titanium dioxide..??), with ALL OTHER THINGS BEING EQUAL!
Mike