For a guy who is armed and who is resisting, the fact that he is armed is indeed relevant.
On the other hand:
A police officer may not seize an unarmed, nondangerous suspect by shooting him dead...however...Where the officer has probable cause to believe that the suspect poses a threat of serious physical harm, either to the officer or to others, it is not constitutionally unreasonable to prevent escape by using deadly force. —Justice Byron White, Tennessee v. Garner[3]