Screws and bore holes of the steel plate is countersunk, but the POM plate is flat, which causes a slight increase of the screw above the plate. This is an issue on the board plastic outer housing's horizontal separator from the F row to the number row, as the slight height increase causes the separator to bow upwards from the tension. the same effect on the numpad side is mitigated as that area is closer to the row separators. A simple change from flat to countersunk plate would solve this issue.

Boba U4T spring swapped to Thic Thock 67g extended springs, Tribosys 3203 bottom housing, spring, stem housing, Keyboard Kustom PE foam, with ~2 layer gaffer tape mod:

Sounds excellent, spacebar has a marbly character but lower pitched from the plastic chassis and dampening, and the long pole sound resonates well on the pom plate for stabilized keys. It def improves over the stock steel K4 Pro plate, but ultimately the plastic chassis keeps it from some of the cooler sounds like making the board sound like its raining, or crab claws etc.

If you want to make the board sound more poppy than the stock sound, but still keeping the low-end then the POM plate is an easy buy, but just consider if the warping of the top housing is a trade off you don't mind.