If you listened to Marcos podcasts, you'd know that he has been very critical of the most of the Macs that have come out in recent years. He remains critical of most of their laptops. That doesn't mean there is not still a conflict of interest in principle. But in practice, I would say he has a track record that proves, that he is not afraid to bite the hand that feeds him.[1] With or without conflicts of interest, there's really no substitute for getting to know a reviewer to find out if you generally share that person's sense of what is valuable and not.

[1] Maybe it really isn't the hand that feeds him. Marco's primary gig is his podcast player for iOS.