I bought a Colt 1911 Officers model on my 21’st birthday ( I actually paid for it 9 months earlier but couldn’t get it till I turned 21) 30 days later I took a hacksaw to it to fit a King’s recoil guide. Since then I have built probably 75+ 1911’s for fun, gifts and profit. My last project 1911 was a Rock Island Standard which still has some improvements to go but I have been busy.
You can see it here: Rebuilding my RIA: The VooDoo that I do
Having gone through everything from Colt’s to Springfield’s to Kimber to “pick a brand” the machining now’a days is all CNC and they are virtually identical. I like Rock Island simply for the history but in general most any MFG that makes a 1911 will give you good service. All can benefit from a throat and ramp job, rarely will you need a slide squeeze. Sights are a tap on - tap off affair get what you like. 1911’s have become LEGO guns much like the AR-15 IMHO if you are willing to work on them.
Cheers,
Craig6