Choosing the Best Email Validation Providers for Work Emails

Is it better to use a Work Email Validation Provider (like ZeroBounce or NeverBounce) when finding work emails in the Waterfall? Or do your trust LeadMagic, FindyMail & those providers in the Waterfall? Had situations when the providers (LeadMagic, Findymail & others) found a valid email, but then it was disapproved from ZeroBounce... and it might have been good as most of those providers have built in verification mechanisms.. Plus saw that several emails approved by ZeroBounce still bounced after