Two part epoxy (the stuff that comes in those double syringe looking things) is amazingly strong and far better for repairing or adhering to plastic than super glue, in most cases. The longer the set time, the better the adhesion, so go for the 12 hour set time and let them sit overnight. Also, degrease all surfaces (with alcohol) that you will be applying the epoxy to and it will never come off. I have never had a repair fail me yet using this stuff, that has been properly prepped first - from plastic to glass, it's really amazing stuff.
various brands that use these kind of syringe thingies