What is the opinion of Reddit about the
YMDK PBT Miami OEM Profile Douhle Shot Shine Through Keycap Suitable for Razer (Razer Bottom)?

Razer’s own PBT keycaps will fit perfectly (obviously). IIRC there are also some YMDK keycaps you can get such as these that were made for Razer bottom rows. Other than that, all the keys will fit.