Data checking

Hi all, I need to transfer 64 bit data from a FLASH to a 32 bit FIFO,
embedded in FPGA, (very slow FLASH access, burst out FIFO to CPU when
FIFO full etc, FIFO has two writes per FLASH read). However, I also
want to check the data has transferred out of the FLASH without errors.

So, assuming 32 bit data operations, is it best to just successively
XOR each 32 bit value over my block transfer size (up to 1M x 64 = 8M
bytes) and compare to a preloaded value, or to perform
a 32 bit CRC (parallel implementation) on each 32 bit value and then
compare?

i.e. which is the most robust method for error detection for this
largish block size, (not worried about error correction).

Regards, Kev P.

Niv