Anyway, why is Byuu even doing that? Redumping a games entire library just for your emulator seems stupid. How many years does he think it took to get as far as it has?
More dumps can't hurt. I've redumped hundreds of games and came up with a handful of differences:
Energy Breaker: previous dump turned out to be a copier hack with hacked "good" checksum.
Popeye (SFC): one byte + header difference. Unsure what effect.
Spot: The Cool Adventure (GB): previous dump had mangled title in the header but somehow was otherwise identical.
Power Racer (GB): dumped from US cart, turned out different than previous "US/Europe" dump.
Sylvestor & Tweety (Genesis): found what was previously identified as a "Europe" ROM turned up on US cart. My speculation (according to a GamePro reader letter from late 1994, stating the game got a last-minute delay before the original planned release due to a publisher change) is that the previously identified "US" ROM was a late beta, and the "Europe" ROM was final. I see they have changed the game status to unverified with that info.