For science fiction fans, the Mass Effect trilogy is a must-play in my opinion.

The legendary edition provides a ton of fixes which make the first game a lot more fun to play on modern PC's. Note that it's still a 10+ year old game, so gameplay still feels a little odd sometimes. It's definitely still worth a play-through for the story though!

The other 2 games have some improvements as well, but they aren't as noticeable. They aged very well in general and are a lot of fun to play.

Another major improvement is the importing of characters when switching between the games. In the past it could be a hassle, but in legendary edition it is seamless and there is no need to move files yourself.

All in all a worthy purchase. Expect to play anywhere between 70 and 120 hours when completing all games, depending on how much of a completionist you are.