OK, FARR is now both faster and more useable! I assume that is the memory retention. FARR now sits around 10MB whereas before it would drop to 3MB then go up on activation.
Starting up FARR (I let my history show on a blank search) still causes about ~1400 disk I/O operations. This is multiple reads of each history item - I assume this is reading the icon. It would be good if this could be cached somehow too.
The disk is still showing lots of I/O during search, but FARR is snappier than before.
This is promising indeed mouser!