Yes, he did get off, but at what cost?
Should it matter what weapon one uses in self defense, as long as it's legal to own? I think not, but some juries don't think like I do. There are cases, but I don't have time to look for them right now, where an "assault weapon" was used in self defense and the subject was found guilty. If they had used another "style" of rifle they most likely wouldn't have faced charges. That's the issue with Gary McFadden, IMHO.
Why use something that stacks the deck against the user? Until it's time to reload, I can be just as "tactical" with my Lever Action, and no jury will vote to convict me if it was a "justified shooting" and I can prove that I was justified in shooting. If I need a long range shot, my 47-70 Sharps will do the job just as well as a "Sniper Rifle".
It's all about perceptions. The average jury member is not a gun enthusiast and only knows what they see on TV and in the newspaper. Why try to break through their perceptions when you don't have to and the cost of losing is so great?
I remember reading about another case where an SKS was used, in Nebraska or Kansas I think, and I believe that shooter was found guilty. From what I remember, it was what we all would call a "justified shooting".
The odds are already stacked against the legal gun user, and people's perceptions play an important part in a trial. What we know the world to be may be vastly different than that of the reality of the soccar mom on the jury.