My info would be that you should tell those people that they don't know what they're saying.
The anthem has a less powerful amplifier in it. though if you are not getting clipping now then amplification isn't an issue.
The Anthem does have different DAC's in it. Will that make it sound better? Maybe, maybe not. Both have room correction. You're really looking at two pretty comparable products though Anthem is probably a high end name, but that means nothing.
The Pioneer does mean more people have it so if you have issues they're easily dealt with.