The original style carbon fibre is representative of what was used until the mid 90's or so by everyone. After about '97 or so, a few of the high dollar teams started to use a carbon with a different weave, made by a different process. From my understanding, this was done to reduce epoxy content (The heavy constiuent of CF) and create a better, stronger, lighter material. Starting in about 2000 or so, most teams witched to the new carbon, making the older stuff less accurate.
I am a huge proponent of CF decalling, as can be seen in my thread with the Mercedes. The old stuff works just fine, and I will use it until my stash runs out, but the new stuff is just goregeous! It has a weave with a gradient, it isn't just pewter/black, it fades from one to the other in one direction (Think north-south), and you can get some really accurate weaves by lining up the patterns and opposing prototypically. The problem with the old stuff, is that, while you can do the above, it still only kind of looks like you have skewed one sheet or the other, and depending on how well you do it, it may not look convincing.
I have a love/hate relationship with the stuff, and while it looks excellent when it is done, sometimes I think painting might be the easier way to go. I also love how when you apply some sol/set and a blow dryer, it shrinks down, with never a wrinkle to be seen. Really well engineered stuff, for sure.
As far as the detail master decalling goes, it is that bad, it didn't form well, and basically looked like a black screen on the part. I don't think it even said in the instructions that came with it that you had to undercoat the part with silver/yellow/brown. I used three pieces, and threw the rest of the sheet away.
I hope this helped, I took too much time away from work for it to be useless :P
Edit: Mercedes thread is here. CF all around, inside cockpit (roof included), undertray-the whole shooting match. I used about 5-6 sheets of the stuff on this kit.
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