North facing is needed for backlit keycaps, and south facing is needed for cherry profile (not the common OEM profile) keycaps. If using OEM/XDA/DSA there wont

North facing is needed for backlit keycaps, and south facing is needed for cherry profile (not the common OEM profile) keycaps. If using OEM/XDA/DSA there wont be interference with north facing. South facing does prevent use of through switch leds with at least OEM profile. Personally, I use south facing since I use SMD rgb and transparent housings with POM keycaps and the leds on the front look nice.