Mass effect 1: story was awesome, characters had depth, felt like the things I did really mattered. Had terrible gameplay. Mass effect 2: all the positives of the first game plus better gameplay and better DLC that added many more hours of gameplay. Mass effect 3. Everything the second and first game had with great gameplay and good DLC with a gripping story all the way up until that ending that marauder shields tried to save us from. The extended cut DLC made it a lot less shitty for me personally. However my favorite has to be mass effect 2 because of how I genuinely enjoy beating it on insanity. Getting that perfect ending after all the crap deaths via those collectors that used shockwave over and over again. So satisfying.