File handling as a whole is much much slower, in my experience.
For instance, a logsearch script using /filter on a large log file (50k lines, I believe) took an average of around 10 seconds on v7.x instead of 2-3 seconds on v6.35.
When log files were saved as UTF16 instead of ANSI or UTF8 then this time was cut in half.
I don't have my benchmarks at hand here, but this was the gist.
