Hi,
I assume it makes sense to provide my recent experience here.
Last Saturday I was handed over my Specialiced Tarmac Pro 2020 with Force Etap Tarmac Pro Disc – SRAM eTAP | Specialized.com
Before that I was riding a Roubaix with manual Ultegra only. That said the overall upgrade is pretty significant.
Nevertheless, I only get outspinned with the 10 tooth cassette at 75+ km/h or more. That is not an issue for my kind of riding.
Interestingly the overall drive train is a little louder than the Ultegra one I am used to. Since indexing is done properly I assume the chain etc is just a little louder.