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!
PrBoom+ for everything. I used to use Crispy but I can’t be bothered to switch between them for Boom and vanilla wads so I just stick to one.