Retainers and Bianators

Hi guys, the girls just got orthodonture stuff done. (Bye bye IPad2!) My eldest is fine with her upper and lower retainers. She's good. She can wear them 24/7 and seems ok.
 
My poor youngest got this horrible beast called a bianator to lengthen her lower jaw. Does anyone have experience with these? The doc says she'll be able to talk with it but I can't see how. It's upper and lower and all connected but not fixed to her teeth, basically everywhere in her mouth. She's supposed to sleep with it too.
 
Anyone have any experience with these things? The retainers seem do-able but this bianator is a beast! Will she really get used to it like the doc says? Is it reasonable to expect her to?