One particular group that I rooted for is Delilah. Their first entry was "Grenade" by Bruno Mars (see video below). It was so powerful that they nailed it and set the bars too high for them to reach. Sadly after, they did not make it to the finals and got eliminated on Episode 8. Another favorite entry done by Delilah is "Whataya Want From Me" By Adam Lambert.
Pentatonix was the champion in season 4. My favorite entry is "Video Killed the Radio Star" and "E.T.". This group is a bunch of kids. Imagine kids with powerful voices. At the start of the competition, they did not really stand out but also not left behind. The group never stepped on the bottom place, not even once. What is good about this group is that they explore and take risk on their arrangement. They have the best beatbox and bass----soooo looow.
I am so looking forward to the next season which will be later this year.
Enjoy the best song in the competition, at least for me. ^_^