I've collected quite a few CRC32 methods and compared them all, it would be interesting to do the same for CRC64 to get the whole range of options too.
"crc-mark-adler-hw" uses SSE4.2 just like your "crc-sse42". The latter one is just very poorly written, since it only uses _mm_crc32_u8() once per iteration (instead of 3 times).
The results are here: https://github.com/baruch/crcbench/blob/master/log.i3-2330M-...