If you are carrying a Glock 20 for personal defense, I am going to guess that a ported barrel is an acceptable configuration...after all, a full house 10mm load tends to get people's attention even out of a factory barrel. I know that I definitely notice the cahnge when I am shooting defensive ammo out of my G20 as opposed to a 9mm.
By the way, I like the little "memory stippling" contact patches behind the grooves of the rail. My G26 has them, and it's a neat little "aid" to assist in getting a solid thumbs-forward grip.
Good luck with the sale.