Thanks to the retro compatibility info in this thread, I swapped out my prev-gen Red FD with a new Red FD w/yaw. It works great; no issues!
My crank is a Zipp Vuma with 9/10 Vuma rings and the chain is KMC X10 SL. Previously, it was hit and miss on a fast shift to the big ring. Sometimes the old Red FD made the shift rapidly especially if I backed off the power during the shift and babied it. Unfortunately, I could frequently hear / feel the chain attempting to claw its way up to the big ring ... usually taking about one full revolution.
With the new yaw FD, it's just the opposite: the shift to the big ring is more often instantaneous and infrequently hesitant. I call it a big win and a reminder that what I had before was sub-optimal.
I was ready to swap out my Zipp 9/10 rings for their newer 10/11 models, but the yaw FD was a less expensive option. I'll do the rings later. I'm happy that it worked out! Thanks for the info.