The Sig is a fine pistol....
but with a 1911 you can customize it to your personal preferences(simple is better), get a .22 conversion unit(Marvel) and if you ever get a powerhouse bug, a Clark conversion barrel in .460 Rowland that throws the .45 ACP bullets at .44 magnum velocities. It is also thinner for easier carry and abit simpler to maintain and repair. There is much to be said about the consistant, crisp trigger pull all the time too.
And the history of the 1911 is hard to beat.
But, it is your money. Buy what fits you best.
I started with a 1911 in 1976, tried everything else as it came out and kept returning to my starting point. Now I just carry a 1911. Now I wish I had put my money into more 1911's, ammo and alot more training instead of trying all the 'new and improved'. But life is an educational process and as such can be quite expensive.
My search for 'what's best' is over, your's has just begun.
Chose Wisely, learn well, carry always(if you can legally do so).
DVC,
Jercamp45