I purchased the AO several months ago and am extremely happy with it.
I bought it over the SA for two reasons:
1. Made in America (though some parts are from Spain, it is machined and assembled in the US, at least the stamp says so. Theres just something about a distinctly American gun that is stamped with "Made in Brazil" on it)
2. Cost ($420, though the SA was just a few $more)
My AO has not come without some problems though.
I read extensively about the AO before purchasing and was aware of three problems some people were encountering with them and of course, I encountered two of them.
1. Failure to reliably feed
I had at least one round from every AO magazine that would not chamber fully.
After some extensive blogging it was obvious the AO mags are junk (or so I was told).
To make a long story short my feed problem was remedied by simply buffing and polishing the sharp edge on the barrels feed ramp.
The problem was NOT the AO magazine.
Along with some new Colt .45 auto magazines, I haven't encountered any feed problems after several hundred rounds.
And that includes many rounds of JHP.
2. Front sight becomes loose
Yep, mine was loose after a few rounds. My 'smith restaked it. A very simple proceedure.
Another problem that comes up is that their repair service and customer service can be better.
I have no experience there as I used a competent gunsmith to do these simple fixes. He charged me $20 ($5 tip) for the repairs.
There are other things which the AO may be vilified for, such as using investment cast. The debate on that is still going on but I will say that some top auto manufacturers also use it. I understand S&W uses investment cast.
Oh yeah, this helped me decide on the AO too-
http://ezine.m1911.org/contents.htm
.........
Phil