I am profiling a large AIR application (Flash Builder 4.5, Flex SDK 4.5.1, AIR 3.1).
How much impact does the debug version of the application have on the profilers performance and memory snapshots?
Is there any rule of thumb - 1%, 5%, 10%,....or is it application dependent?
In terms of absolute numbers, it depends on the code. IOW, you cannot use the numbers you see to determine the actual numbers of a release build at runtime and there is no rule of thumb to use to guess at it.
In terms of showing you what the problems will be in your release build, there is no effect worth considering. The top issues in the debug build will be the top issues in the release build. Maybe down at the bottom half of the list it would shuffle depending on release build optimizations, but if you are noticing a problem, the top items of profiler will show you what it is.