I normally wouldn't change a registered name but when the breeder names 2 horses the same name in consecutive years, yeah, I'm going to change the one I bought.
Skip N My Assets was named Skip N Seall, 2010 Cremello Stallion, he has a 1/2 bro, Skip N Seal born 2011, palomino colt. Both colts are from the same mother, Bucki Seal, but different sires. My Skippy is by Dun Up The Assets and Skippy 2 is by Skips Beyond, so I thought the Skip N Seal fit him better anyhow.
So, I honored the QH tradition of using sire & dam names and renamed my Skippy, Skip N My Assets. I think it would be worse luck to try to show and market a stallion in the same market as a 1/2 brother with the same name. Talk about confusion!
AQHA was very helpful, and once they were able to confirm he met the criteria, issued new papers. I think it was $50 or $55, well worth it to prevent any future issues. I'm not sure about their data base, but in the Arabians if you change a name, the original name shows in parentheses and will come up in an inquiry. I'd hope that QH does something similar, so a changed registered name wouldn't become a problem.