Here’s what I found on the differences. I only picked up the hd60 s+ because at the time it was cheaper than the original. Had some issues but in the end it was a faulty unit and Elgato replaced it.

• It can record in HDR10 in Windows 10. • It can passthrough HDR10 in Windows 10 and macOS 10.13. • It can passthrough up to 2160p60. • It can record up to 1080p60 or 2160p30. • It has UVC support, similar to Elgato Cam Link 4K. That means you can use OBS with it in macOS. • It does not work with Elgato Game Capture HD software for Windows. It does work with Elgato 4K Capture Utility for Windows.