I also agree with others that for most generic photographic purposes the CC24 is not only easier to use but potentially actually better than the SG (for a number of practical and technical reasons).
Hi Mark and Andrew,
A DCP camera-referred profile can be based on virtually any target out there. In fact software such as DcamProf/LumaRiver have reference values for most commercial ones built in, see the attachment.
The key word in my statement above is 'generic', as opposed to 'specific'. Anders Torger and others could speak better than I about this (you know who you are, please feel free to chime in), I am not an expert, but:
From a practical perspective the SG is very finicky to set up and deal with, as DP alluded above, because its semigloss finish tends to create glare, let alone specular reflections, that can create havoc on the profile-creating math even when one is being careful. Some such software for instance has an option to ignore the more troublesome semigloss patches in the SG. Anders quips 'Due to their difficulty during measurement the end result is often a worse profile than using a matte target.'
From a technical perspective, one has to keep in mind that 'accurate' dcp profiles are applied very early on in the long processing chain that leads to the final image. No matter how many patches are used we are simply sampling the same gamut more or less frequently. The profile designer is presented with a trade-off: produce very accurate, tight fitting tones for the very specific setup that however may rip at the seams if the subject is significantly different (this of course might be quite appropriate in 'specific' applications); or produce a slightly looser fitting, though more robust, profile that will stand up better to the type of image and processing in a 'generic' photography situation.
It turns out that for generic photography the matte CC24 is harder to mess up and quite capable of creating such looser-fitting though more robust profiles. So for most of us shooting the landscape without special needs a CC24 is actually a pretty good, convenient choice.
Jack