I have the Tru Glo F/O on my G34 then went and bought a LWD 4 ported barrel. Put it in and was so happy how it looked. I then noticed that the 4th port was sitting directly below the front sight tip. I immediately thought that it would melt my front sight. So I call the guy I bought them from (Glock Certified) said hey man do you think that I will have an issue with melting that front sight. Of course he says no unless you shoot rapid fire. So needless to say DO NOT use F/O front sights if you have a ported barrel. It melted the F/O tip within 5 rounds. Going with the T.A.S Sights and I will let everyone knows how those work out.