That was an interesting read... You can find it linked here:
LINK
There are several issues with the study listed. Primarily - Your interpretation is wrong relating errors... All of the databases listed in this thread contained errors, including both premium and free version of epocrates. I'm not sure where you were reading there were no errors... maybe you could post up a link (the linked study clearly states which databases had errors, 37 total were found). As to epocrates doing the best on PDA's... that article referenced is from 2006. I'm pretty sure the scope of PDA databases has changed since then.
Secondly, ACPE is not considered an authority on anything except ensuring pharmacy schools meet a minimum criteria to be certified. Note that does not include informatics. It's great they can provide CEs - but I would certainly question the source in this case.