Good luck in your quest for a 19" cock, looks like your'e in fantasy land as what you would take would be 6" minimum 8' max so thats 11" waste and youl"ll never get it hard enough to sustain a good erection.
I'm more than happy with my 7" hard cock with a 5.5 - 6 inch girth depending on how horny i am. Have pleasured many a woman and bought to multiple orgasms. As the saying goes Quality not Quantity......