My favorite and most used is PRBoom+, more specifically the UMAP info fork, since it brings many QOL and modern features compared to the now abandoned and kinda old last official version.
Other source ports I use and love: Eternity Engine, Crispy Doom, DOOM Retro and GZDoom if I’m feeling ““funky””.
Very curious to know lemmy’s favorites!
The one I’ve been using is International Doom, as it feels similiar enough to the original and it has controller support for my Steam Deck.