It was able to keep me, someone who can't pay attention on a game for more than an hour, to be so engulfed in its environment, story, and gameplay to sit for 3-5 hours each session. Below Zero has a lot of similarities to the original, but with the whole new terrain, new vehicles, and new story, it feels like a totally different and new game itself. It adds onto previous story lines and lore, adds its own lovable characters, and makes for a great experience! (Plus the dozens of articles on the Wiki and interactive maps)

My favorite thing in the game has to be the seatruck and the dialogue between Robin and the other characters (plus PDA entries):
The seatruck can be used as an agile sub, just like the seamoth, or as a mobile base with more capacity and customization than the cyclops (Although I do miss the cyclops's pilot HUD). Its even got its own dock, which makes entering and exiting so much better and more intresting (and keeps your prawn suit on the dock!)
Robin is a pretty relatable character in the sense that she's weirded-out by the random ♥♥♥♥ that happens, and also is very much against Alterra. Her interactions with the other characters, such as AL-AN and Marguerit (love her return), are funny and informative. She just makes sense.

TLDR; Below Zero kept my attention and my enjoyment never faltered (even when I was lost). Def try it out!