Three of us bought Springfield GIs. Two were the Lightweight Champion model, one was the full-size government. One of us was happy and still has his Champion.
Mine frequently failed to feed and failed to extract, even after 600 rounds. I sent it back to Springfield. And let me say here that their customer service is nothing short of stellar they were friendly, professional and prompt. They polished the feed ramp, replaced the extractor, and either polished or smoothed out the chamber. It worked better, but I still didn't enjoy it at the range, much less would I have trusted my life to it.
I have heard good things about the Mil-Specs. If they're true, they would be worth the extra money.
And yes, the sights on the GI are tiny.
"An armed society is a polite society." Robert A. Heinlein
"After a shooting spree, they always want to take the guns away from the people who didn't do it. I sure as hell wouldn't want to live in a society where the only people allowed guns are the police and the military."
William S. Burroughs