#7. So Cool
The first entry on the list is also the oldest, as "So Cool" came out in 2011. This was the first of a string of solid releases for Sistar, and "So Cool" utilized many of the elements that produced great music. Catchy dance moves, snazzy instrumental, and high-flying vocals from Hyorin are (understandably) Sistar's recipe to success and this song embodies that. "So Cool" is also notable for having one of Bora's longest raps in their / her resume, which is great! Bora fans know the struggle of Bora's own struggle with lines in later releases.
#6. Ma Boy
Looks like I'll never get the Sistar19 comeback I wanted. This was an anticipated subunit and for good reason: Hyorin and Bora are amazing so putting the vocal juggernaut and rapper together is a good combination. While future songs would heavily imbalance line distribution ("Gone Not Around Any Longer"), they didn't make that mistake with "Ma Boy," and gave Bora some singing opportunities, or at least gave the impression or disguise that she was. You'll notice that this song also has another solid rap from Bora, which is always a plus. In fact her rap in "Ma Boy" is probably her best in a vacuum. And one does not think of "Ma Boy" without those glorious body rolls.