I wasn't aware that 303 cleaned; I thought it just protected.
I liked Vinylex on my Lexus, but prefer 303 on my rhinoskin dash in my Audi.
Vinylex does clean. Aerospace 303 has UV protection. I also like how you can use it on leather, whereas you can't with Vinylex.
Vinylex has a medium sheen, Aerospace 303 has very low sheen. I have bottles of both 'cause I like having options.