I switched out my old Ultegra crankset to GRX (FC-6800) as I wanted lower gearing. As I learned that the GRX chainline is slightly different and it would be difficult to keep the old Ultegra FD (FD-6800) from rubbing I also changed out the FD to this GRX810. It's important to find and download the Shimano installation and adjustment instructions as they don't come with the components any longer. Anyway, they made if very easy to install and to adjust to prevent rubbing at all chain angles.
The GRX FD-RX810 seems very much like the 105 FD-R7000 on my new road bike. It shifts quite nicely - smooth and easy. After 26K miles the old Ultegra FD was pretty beat up and ready to be replaced anyway.
Switched from a 105 to a GRX crankset on my gravel bike and was having shifting issues.
Swapped in the GRX derailer and perfect shifting.
A bit tricky to set up with wide range cassettes and wider chain line.
The derailleur does not have full instructions, but you can find them on the web. Great derailleur. Shifts great, trims well. So far, very sturdy.
