NOOO WAAAYY!! NEVERRRRR!!! That would be nothing but fooling ownself, or could anyone ever be honestly proud of that kind of 'own' art?? For gods sake..!
If the sword of the deadline is hanging above you, these adresses may be a good way out of your dilemma. But, as Speakinstone stated before, using your own material is far more satisfying and makes you more proud of your work.