From what I know about the GI series, it's pretty much Springfield's attempt at making a copy of the WW2 USGI 1911a1 without it being an exact "replica" i.e no military markings ect. But they are dependable and from my experience from firing one with a Union Signal 1911 for comparison. They felt about the same and shot the same. Though the SA GI felt like it had a tighter slide to frame fit. I also know that they have forged frames, slides, and barrels. Some of the other smaller parts have Metal Injection Molding, but I haven't heard of anyone complain about the parts breaking.
The gun also comes with an internal safety lock on the mainspring housing, and I have heard you have to change out the mainspring itself along with a few other parts, should you decide to change out the mainspring housing. Also the firing pin used in the GI are from a 38 super firing pin and not a 45. So keep that in mind as well should you change that out.
One more thing worth noting is the guns are made in Brazil or are originally from Brazil by a company called "Imbel" and the newer G.I guns will bear "Made in Brazil" on it's frame. But again the quality is bar none for a good entry level 45, and being it's made with forged parts is a big plus too.
I have two G.I. 1911's, one being a SA Light weight Champion G.I.
Although I've had to send both of my Springers back in for repair due to manufacturing defects that did not affect the operation of the guns, I would still recommend them to any one because I've yet to have a failure of any kind and the SA customer service is easy to work with and will take care of manufacturing problems, even if you bought it used!
The sights are a little hard for me to get use to but I like them for the low profile'ness of them, put a little white paint on the front sight and they're good to go!
They are great entry level 1911s. Fit and finish is good, & they run well. The only downside is the tiny sights. I have a couple of them I plink with. My TRP is my EDC.
I have one and I think its a great pistol. I had a stove pipe with mine within the first 20 rounds, but after that, the next 200 or so have been flawless. I agree with the others about the sights being small. I think a mil-spec would be better for the sights alone, but if you want the WWII look, then this is the perfect pistol.
I am looking for an entry level 1911, and I do like the look of the GI with the dark grey or the OD green. I'm going to look at the mil-spec now. I just don't want to spend a fortune and find out that 1911s aren't for me.
Get the cheapest one they offer (basic GI model). Shoot the snot out of it. Throw it in the box when you're done at the range. Clean it only when necessary to keep it running. Don't let it rust. Let it get beat up and build some character. You'll love it.
Later on, if the "I want more" bug bites, you can send it off (or do it yourself) to a gunsmith for a "carry package." I'm talking about internals only (NO frou frou finishes, melts, checkering, grips, etc.) and maybe some sights. You will then have a reliable, cool looking 1911. I should know, I did it and I love mine.
My 2 cents on the Springfield GI model: It's a great, relatively low-cost platform to start to learn gunsmithing if you are interested in that. It's got a functionally sound forged frame and well assembled at this price point, which is always a good start for projects.
I would check out the Mil-Spec version (for a few more dollars), if I remember correctly it has a lowered / flared ejection port and a slightly wider magwell, both options might be worth the extra few bucks.
Of course the disclaimer must be added: Make sure you research and understand EXACTLY what you are doing when you make changes to any gun. Always test with 1 chambered round only. A .45 going full auto is extremely dangerous and a borderline "religious experience" (That's how it was described by the poor soul who it happened to).
I love my G.I Springfield, Never had a single issue with it. Very reliable weapon.
I thought about purchasing another one an playing around with to see what the gun is really capable of doing with least amount of mods.
I kind of like the GI because of the "no frills" look to it honestly. I think the WWII look and feel seems cool, and if people were shooting things with sights like this all those years ago, seems like I should be able to figure it out. I want to stress I don't want it for an EVERY day carry, just sometimes. I like the historical factor, even though it's new.