Firstly, it's devoid of setting. This' more a personal preference thing, but I dislike games that are too linked to a setting; I'd feel odd for example, saying: let's go play Star Wars!, etc.
Secondly, it really is the best system for my group's sci-fi needs. What's more efficient than pairing an attribute with a skill? Str d6 + Brawl d4 = perfectly intuitive and rules lite.
Thirdly, the elegant rules set allows for story and narrative over crunch. Determining the appropriate dice rolls to determine virtually any action is an intuitive snap.
Fourthly, CORTEX covers small to large and beyond scale damage with a simple 1:10 scale. No problems.
Fifthly, The vehicles, be they motorcycles or starships, follow the same rules set as characters and npcs. Simply brilliant.
Sixthly, plot points are an amazing way for players and GMs to create a truly collaborative story. Yessims.
As you can see from above, I love the system, and find those who criticize it to be odd.
Seriously though, pour moi, there's truly everything to like here.
