Teens, not Tweens...but let's get one thing clear!
I am on the inside of this show....There are NO BISEXUALS IN THE GROUP. You have been misinformed by poorly written and sleazy articles meant to only report what sells a headline rather than the truth.
As for the age appropriateness of the show, it's the cleanest on MTV; however, with such shows as 16 and Pregnant, Jersey Shore, and Teen Mom it's not a hard task.
The Electric Barbarellas (given the rating TV-PG) could be on cable channels such as TNT, TBS, USA, etc. The same "salty" language can be seen on any reality TV show on network channels such as The Bachelor, The Amazing Race, Survivor, and America's Next Top Model.
My best advice: Don't believe everything you hear because as you know, negative press will always sell better than the truth. Watch an episode for yourself at MTV.com so you can make your own decision on whether or not you can let your teenager view the show.