Mismatching bitness of process and loaded assembly Assembly.ReflectionOnlyLoad(byte[])

I am using Assembly.ReflectionOnlyLoad(byte[]) to load a managed assembly from the .dll file's raw bytes. My process is 32 bit, but the assembly I load may be 64 bit. This appears to work, but are there any gotchas? What are the implications of mismatching bitness like this? I can't find any good information about this on MSDN.