Regarding the thread title, I wasn't sure if the Swap attachment is considered a spoiler.
Basically, I thought Swap was a cool idea. It's a simple concept that added a lot of fun to exploration and gave the post-game a fresh feeling for the old areas. However, I wished there was a key binding for switching weapons. It was a nuisance to have to constantly navigate the menu every time I entered another area with enemies. --- You don't have time to ponder such questions, as Bruce Willis has just grabbed a jet plane.