From my perspective as a Mac user, one who primarily uses Carrara as a no-frills modeler (and only secondarily as a spectacular render engine), the movement from 3 to 4 to 5 has been marked by an increasing number of cool tools but a decreasing amount of core functionality. Little things like the way duplicates reverse their surface normals, group names are randomly deleted, welding operations become slower and slower to perform, and of course random crashes, means that for all the new toys I can get almost as much modeled in a earlier version. As a Mac user who attempts to actually finish and export models for use in other applications, my only remaining interest in Carrara 6 is if it offers more and more intriguing render options. I simply do not trust the current team to deliver a non-buggy model engine I can use on a daily basis, without having to deal with long-winded work-arounds and crash recovery routines.