That's a hard one to put a definitive answer to. I see the merits in a GI 1911 like a Rock Island or S.A. Mil-spec, I had an M&P 40 and loved it, you could also list the Beretta 92 and PX4's, I'm sure someone will mention Glock. CZ 75's are badass and so are their clones by Tanfoglio, Springfield XD's have their fans.
The best all around hand gun is the one that tickles the individuals fancy. I prefer my S.A. GI 1911 for it's old school looks, charm, handling, and accuracy.