Hard to tell, since install.wim is ~90% of the data on the disc in a single file, it could be different by a single byte, or there could a whole bunch of differences, no way to know unless the content ...
This is the CRC for install.wim from the "Windows Vista Final English DVD Images (x86 and x64) 6.0 Build Final media images for Windows Vista English DVD's" x86 .iso:
Topic: 
I checked CRC for MSDN patched BILLGATES release.
