The P1 is a horrible pistol, indeed. I´m glad we replaced them in our armed forces with the P8 (H&K). We always used to say "you have 8 shots to miss the target - but one throw to do the job!"
Did you ever experience problems with the metal of the slide cracking? Some of the late-production WWII P-38's had this problem.
BTW, my experience with the Berretta P9 (current US issue) is that it has the same fine ergonomic feel as a 2x4 piece of wood.
The SIG is a great pistol but I cut my teeth on the M1911. I tried a Glock and thought it was "just OK". Old habits stay with you. Now, the Browning P1935 "Hi Power" is a pretty nice gun for a .380 magnum...