Basically it is always better, if on Windows x64 use the corresponding x64 version of the program.
I have tested NonCompressibleFiles on Win x64 with the x64 version and x32, here is only a small speed advantage in the x64 version, when create non compressible files.
So, the speed advantage is already measurable, but not really crucial for the use of 64-Bit NonCompressibleFiles version!
Here is a picture from win 8.1 x64 240 MB per second, when create non compressible files!
FAQ 1: Updated on: April 4th 2014 22:50