Hi, I'm Mark and just placed an order for an R5, seling my 5dsr in exchange, but keeping a 90d for now. Hopefully some beach and South Downs images to come!
... EF-RF adaptor on order, but it's probably on the Ever Given . When I do get it, I can use my 105 macro and 100-400mm (the RF versions either don't exist or are too expensive for now, and by all accounts the EF lenses still work well.
Yes those EF-RF adapters are like gold dust at the moment. I got lucky with Wilkinson Cameras a week back as they had a few in stock, they were soon snapped up though!