Ask HN: Binary versioning for designers?

Wondering what the HN community thought of a startup I'm working on. Tentatively I'm calling it DesignFiles.io, and it's a combination desktop and web app that lets designers check in/out projects they're working on. Designers can save comments with a revision and control access to their projects.

There are tons of so-called "digital asset management" tools out there that combine some form of versioning with reviews and other features, all of which are too heavyweight for many of the teams I've worked on. The sweetspot appears to be somewhere between Dropbox and these enterprise tools.

In terms of implementation, I have about half of the product built. The desktop app saves files to S3 (using temporary credentials via a token vending machine). The web app then monitors the usage. A client can have an unlimited number of projects and team members for a tiered monthly fee.

I'd love to get feedback on this. Thanks!