Question
Is there any reason to use 64 bit WinPE instead of 32 bit WinPE?
Answer
Currently, the only known reason to use 64 bit WinPE instead of the 32 bit version is if you are doing a scripted install of a 64 bit Operating System.
WinPE x86 (32 bit) will work for imaging all types of processors.
Another advantage of using WinPE x86 is the possibility to deploy Hardware Independent images with Deployanywhere, please see: TECH41109