Don't use armor all or son if a gun. Vinylex is what you need. It doesn't leave an oily residue like those products and it moisturizes the vinyl deep into the fabric. It also has uv sunscreen built in to prevent sun fade and drying out. I have actually used vinylex to treat chalky dry rotted interior panels and bring them back to life. Good stuff!
Not to mention when you use it, you get a nice clean surface that is factory fresh, not a greased up interior. Save the oils for the women in scantily clad bikinis...
Armor all and the likes will dry out your vinyl and plastics over time. I'll never use those products again.