Kind of rude sarcastic response don't you think?
No, not really. Well I don't think it was rude and sarcastic towards you. That certainly wasn't my intent anyway. If anything, I was merely trying to point out the fact that the design is not very complex, nor should it be difficult to build. So I see no reason to expect one of the CA guns to not function correctly when it comes to keeping a quality standard load in the subsonic level.
I have a CA89SD that I run with my Fleming Sear in an SEF pack. It was built up by Andrewski and has a re-timed hammer. The combination, in my case, works very well. And the Wolf ammo that I shoot through the gun is very quiet. I've examined the barrel porting and compared it to my dealer's factory HK MP5SD. They look just about identical.
I guess I was a little surprised that anyone would post what you did. With the exception of a few people who have had fake SD guns built with no porting on the barrel, I haven't heard a single story from anyone at all that they got a clone SD that was ported enough as not to keep their standard rounds subsonic. Have you personally had a problem with this, or heard of someone who has?