My understanding is that you shouldn't be using HW accelerated encoding for any archival purpose except realtime capture. The PSNR/bitrate is much lower for HW

My understanding is that you shouldn't be using HW accelerated encoding for any archival purpose except realtime capture. The PSNR/bitrate is much lower for HW encode, but the encode rate is typically realtime or better. That's a great tradeoff if you are transcoding so that a device with limited bandwidth can receive the video while streaming, or so that you can encode a raw livestream from a video capture or camera. It's not so great if you are saving to disk and planning to watch multiple times.