As a creative director I used to work a lot with tools like frame.io, wipster & filestage. The past 6 month I worked with wipster and filestage more frequently, so I'll share my experience with those tools. I like the fact that clients don't need to sign up to give feedback eather with Filestage or Wipster. That's what my clients love, too. When it comes to UX, imo Filestage is ahead. The simplified design made it easy for me and my clients. No training period needed! What Wipster makes preferable is their integrations with vimeo. To be honest, I didn't used it that much just bc vimeo is not my favorite channel, but I know that this could be important for many clients. Cheers!