As fan as reliability and accuracy I would put my PT against all but the best custom 1911s. Mine is 100% reliable and I can shoot 2" groups at 25yard.
I do own a couple more expensive 1911s and for me the difference is in finish. Taurus blue is more like a black paint coating and inside it will have more machine marks than some 1911s. It is one of the best 1911 buys out there, has a forged slide and frame and lots of options that are not std on most 1911s. I have been very happy with mine.
Knowing the quality of Sigs, I am sure their 1911 would be very nice also, I just don't care for the look of their slide.
For me, the only negative I have with my PT1911 is that Taurus used their own cut for sights, if they would have used a more std cut, sights would be much easier to replace. They are the second most replaced part on a 1911.