There is none that understandeth, there is none that seeketh after God. 12 All have turned out of the way; they are become unprofitable together: there is none that doth good, there is not so much as one. 13 Their throat is an open sepulchre; with their tongues they have dealt deceitfully. The venom of asps is under their lips. 14 Whose mouth is full of cursing and bitterness: 15 Their feet swift to shed blood: 16 Destruction and misery in their ways: 17 And the way of peace they have not known: 18 There is no fear of God before their eyes.
This is by the way, a citation from Psalm 13; Psalm 14 goes on to describe men who walk "without blemish, and work justice".
St. Paul's "all" is a literary device of generalization, like "all Mexicans have dark hair". Surely some people existed both in Judea and in Rome who were not bloodthristy murderers. It is not a prooftext for Mary's sinning.
Romans 5 does not even describe actual sin; moreover, "all" in verse 12 becomes "many" in verse 15. In other words, there, too, we deal with a generalization with implied exceptions.
Nobody denies that Jesus is Mary's Savior. It is He Who made her without sin.
So what you're saying is because I am a Christian, that Jesus Christ is my savior, I am without sin and equal with Mary?