Re: Aluminum & steel?
The Taurus 92/99 (a copy of the Beretta 92 made on Beretta tooling in Brazil) that I have had for decades has a steel slide running on an aluminum frame as does my Sigs P220 and P225. None of these guns has shown any signs of excessive wear. But it of course depends on using the correct aluminum for the frame. Steel on steel is better yet, as done on the CZ family of metal guns. The worst has to be PLASTIC guns. Give me all metal anytime.
I personally would not own a aluminum framed 1911 because it is not "correct" in my eyes. I'd wait for the all steel Taurus if I were you. This is a big seller for Taurus, I think, and it will be available soon, I would hope.