Easy for deploying different stages with different build parameters, less of a PITA than the AWS S3 + cloudfront distributions. It's annoying though that we've basically been forced to use their DNS solution since we need custom URLs for branch deploys.
I didn't have any issues with buy-in since we were only a few people at the time and basically got the ok as long as there wasn't any downtime in the transition (which there wasn't).
Can confirm netlify DNS hosting was never a requirement for branch deploys, using your domain name (staging.you.com) or netlify's (staging--yoursite.netlify.com). This article shows how to configure using other DNS hosting: https://community.netlify.com/t/support-guide-how-to-use-net...
I didn't have any issues with buy-in since we were only a few people at the time and basically got the ok as long as there wasn't any downtime in the transition (which there wasn't).