Installed mine last night..
Clear improvement in good conditions. 80m FT8 went from being a horrible mess to visually and audibly tidy.
FAST setting will reassure You of it's speed with some audible pumping after periods of FT8, and on some loud broadcast stations - fairly hard knee stuff.
I tried to cut corners by not installing the supplied switch, this was a mistake - You really will want the option to change between FAST/SLOW/OFF if You intend on doing anything other then digimodes IMHO.
I had a previous s-meter mod, so a simple move of A7 from that to the pad on the board kept it running without any drama, as long as it's in FAST or SLOW mode.
All-in-all, this was worth doing. Looks well 'borg' too sitting as it does on the motherboard :)