I own a Taurus PT1911 AR as well and love it, along with a couple other . I have also owned several other brands, and the bottom line is the same, ..there's a reason why the pistol is still being used after 100 years of service.
If your looking for one just to have, then literally go with what feels right in your hand, (I say just to have & NOT carry) just having one don't have to worry about it being too big I personally recommend getting one with a rail if you ever think about getting a laser or light.
However if your looking for something to carry, consider size & weight of the firearm. The full sized full metal framed ones (such as my Taurus) are wonderful, but they are a brick to carry and for me (i'm 4"10 and about 160) after a day of carrying it in my hip pack i pay for it. If your anything like me i'd fully recommend a 4" (i've heard nothing but great stuff on the new Kimber Crimson Carry)...
They are wonderful very straight forward firearms I personally love them, but the bottom line for you is what feels right & what your familiar with.
Hope I could help...in some way