Definitely changed the pitch of my keeb. Love this guys work.
A white and black foam is sandwiched between the plate and the substrate, which will definitely improve noise and feel smooth when typing. In addition, when placed on the bottom plate was a more quiet effect.
Worked out great. Foam was modified by MKUltra to fit the non-hotswap version. The extra thickness did make soldering a little trickier as I did have to keep some pressure on while getting the first few switches soldered. Really, no big deal though. Great stuff.
I had to trim the foam a bit around the stabilizers, but once I did that it was basically a perfect fit. Slightly thicker than the gap between the PCB and the plate, but I think that just helps dampen sound from the plate.