A few photos comparing the 2 C6.R's by Carrera and SCX. Both are great models and are well made by each of the company's. Each are worth the money and I consider them high points in recent releases in quality of detail in modeling and quality in workmanship.
My photo from the ALMS race at Lime Rock in 2005 for reference.
Photo above, the SCX is on the bottom, the Carrera on top.
The SCX is on the left, the Carrera on the right.