AllBreedPedigree is somewhat notorious for having incorrect or downright fake entries. THe “sim breeders” people it rather heavily… Between them and the simple fact that ANYBODY can go in and alter or edit any horse entry, well, it’s not high on my personal list of trusted sources.
That said - I still have my AQHA membership, and once in a while I will run a pedigree check for some reason - you get ten bucks of searches free each month, rarely do I use it all.
IF you have an account with equineline.com you can get QH pedigrees, race and show records there too. Yes, they do charge for the service, but only when you use it and the fee is nominal, to say the least. I think that actually equineline’s fees are same as AQHA - but you do not need to have an AQHA membership to access the service, just pay your bill when it shows up in the mail! 