Here we have my HK Tactical .45acp with the Gemtech Blackside. I have to say for the money I am pleased. It's very quiet and accuracy with 230 grain ammo is excellent. The .45acp is ideal for suppressing since it is subsonic. This way if something bad goes bump in the night, we need not bother the wife's slumber. You need to get the adapter to use on Mark 23, annoyed with HK for reversing the threads...