dpreview has just completed the full review of recently released Sony a7R IV (B&H Photo Video/Adorama/Amazon) full frame mirrorless camera today. It received their gold award and 91% overall score. Currently the best camera reviewed by dpreview.
The new announced Sony a7R IV now shipping today, currently out of stock everywhere, you can check pre-order options at B&H Photo Video/Adorama/Amazon. dpreview has already add a7R IV to their studio comparison tool, so you can compare the new a7R IV with other related cameras.