Came here to endorse the NanoKVM USB. It's a great little device. Wendell made a video[0] on it. The web interface is super handy.

I keep one in my tool bag and I've been meaning to buy a second one for a dedicated crash cart.

I can't speak to the Kiwi or the Openterface as I haven't tried those.

0. https://www.youtube.com/watch?v=SAbyQcpR-yQ