(Billboard)Considering the Academy of Country Music Awards celebrated its 50th anniversary on Sunday night at the Dallas Cowboys stadium, it was bound to be bigger than any previous year's ACMs. Plus, as hosts Blake Shelton and Luke Bryan were quick to point out, everything is bigger in Texas. Billboard: 2015 ACM Awards: See All the Photos . But bigger isn't always better. Here's our breakdown of the 10 best and 5 worst moments at the 2015 ACMs. The Best . Eric Church & Keith Urban provide an opening wallop . With a full stadium and millions of home viewers watching, two of country's leading men successfully lit the fuse for the 50th annual ACM Awards with a slick joint kickoff performance. Eric Church's "Pledge Allegiance To The Hag" was a fine throwback, but Keith Urban's powerhouse "Raise 'Em Up" lived up to its title -- and then some. Setting a Guinness World Record . Not only was this the ACMs biggest audience ever, but the 2015 ACM Awards brought in the biggest audience for a live TV awards show ever. Now that's how you celebrate half a century. Reba McEntire demonstrates how it's done . During a night that found a couple performers sounding a little weak in the vocal department, Reba McEntire showed the entire Cowboys stadium -- and many younger singers who don't have half her energy -- how it's done. Reba is eternal. Taylor Swift singing in the audience . Whether it was during Eric Church or Martina McBride, T-Swift was heating up the audience by singing and swaying along to country staples. Taylor might have gone pop for "1989," but she was deep in the heart of Texas for this annual country extravaganza. Billboard: 2015 ACM Awards: And the Winners Are... Garth Brooks' All-American salute . During Brooks' performance of "All-American Kid," the country giant welcomed a slew of U.S. military representatives into AT&T Stadium, in an emotional moment that put the red, white and blue front and center. Brooks ended the performance by saluting the U.S. armed forces "who are here and are all around the world for protecting our freedom," and also shouted out his home state of Oklahoma, who are grieving 20 years after the Oklahoma City bombing on Sunday. A truly classy moment from one of the best ever. Taylor Swift's mom makes an appearance . Sure, Andrea Swift's presentation of a special award for her daughter came with a fun origin tale about the creation of "Love Story" and some lovely words about the 25-year-old superstar. But the sight of the elder Swift -- just days after Taylor confirmed that her mother had been diagnosed with cancer -- walking to the podium was more than enough to yield one of the night's most poignant moments. Christina Aguilera joins Rascal Flatts . Aguilera is far from country, but with a voice as malleable as hers, she can pass for a song or two. After singing a bit of the tune she did while guesting on Nashville, Xtina joined longtime hitmakers Rascal Flatts for "Riot" from their recent album "Rewind." Aguilera and Gary LeVox trading vocals was the rare unexpected artist pairing that actually worked. Miranda Lambert domination . In addition to kicking ass during her "Mama's Broken Heart"/"Little Red Wagon" medley, Lambert justly owned the night when it came to awards. If there's one thing the country community loves more than Miranda Lambert, it's giving Miranda Lambert awards. Billboard: Watch Little Big Town Bring Provocative 'Girl Crush' to ACMs . Little Big Town don't back down . Despite some mild controversy over their song "Girl Crush," Little Big Town brought the poignant ballad to the awards show, giving the ACMs one of its more melancholy moments. Jason Aldean comes on strong . For a night featuring some shaky vocals, Aldean brought his silky yet powerful country croon to the ACMs during a massive medley. It's hard to see an audience get weak in the knees when you're watching at home, but it's fair to assume that's what happened during his performance. The Worst . Tony Romo . The Dallas Cowboys QB was understandably a little stiff on the mic (athletes usually aren't the most charismatic public speakers) but the whole gag with Shelton asking Romo to toss Bryan a pass went on waaaaay too long. On the plus side, Bryan caught the pass. On the other hand, there was a tired play on words about balls. The length . Three hours for the 50th ACMs? Sure, why not. Three and a half hours? That's pushing it. They could have shaved off the last half hour by cutting a couple of the performers who only sang half a song, and shortened a few of the massive commercial breaks. All of the Milestone Awards . Taylor Swift was given an extended honor at this year's ACM Awards, but some of the Milestone Awards -- especially those given to Reba McEntire, Kenny Chesney and George Strait -- seemed rushed for the country giants they were saluting. It's understandable since 2015 is the 50th anniversary of the ACMs, but sometimes, less (recipients) is more. Steven Tyler's facial hair . See link. Twitter calling out Taylor Swift . Plenty of country fans went after T-Swizzle on Twitter, berating her for attending the ACMs after "abandoning" country music for pop. The truth is, Swift has just as many country classics under her belt as any other artist in her age range. She might have moved to pop, but don't underplay her importance to the genre that birthed her. ©2015 Billboard. All Rights Reserved.
ACMs celebrated 50 years Sunday night . Best moments: Garth Brooks, Reba McEntire, Taylor Swift's mom .