Been looking at these for a while and though currently 'awaiting stock', it says Delivery is available 'on or before Wednesday 29th April' for $4.99 and it's $45 off the usual price of $299. Not a bad option.
According to Elgato, the difference between the two HD60 S vs HD60 S+ is:
• 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 (see this article for more details).
• 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.
Suggest using PCIe if possible to avoid USB bus.
USB can be irritatingly unstable with bandwidth issues and general flakiness (device stops working, prevent POST occurring if device crashes). USB controllers vary in flakiness unlike PCIe.
Also Elgato is the leader in consumer capture cards meaning Avermedia is sometimes much cheaper but I don't know for this particular feature set.