I can't adresss the DAO models, 4583/4586 as I only shot 1 example many years ago and as I recall didn't care for the trigger. The difference between the 4583 and 4586 is that the 4586 is all steel construction vice the 4583's aluminum frame. The 4583 was also produced in much smaller numbers than the 4586. Both are excellent pistols and you would be well served by either gun.
As to the 4566, I carried one for 11 years on the job and have shot many different examples for many thousands of rounds. So I will opine.
The 4566 is all steel construction. The version of the 4566 with an aluminum frame is the 4563TSW. There were a handful of 4563's produced by the Performance Center as well.
The 4566 was produced in 8 different variants. The original with hooked trigger guard and flash chromed hammer and trigger, the LE SPECIAL with spurless hammer and laser etched markings rather than roll marks (many of these were the decock only - the ambi safety springing back up after decocking the pistol), the 4566TSW, the integral rail 4566TSW, the melonite 4566 (rare), the melonite integral rail 4566TSW made for the WVSP (rare), the Performance Center 4566 / 45CQB - APPROX 100 made, and two short runs of 4 inch barreled 4566's from the Performance Center (18 and 10 pistols in the two orders.). These has 45CQB features but were not 45CQB guns as they preceded them by around 18 months. The batch of 18 having black coated slides on stainless frames. These were made for LAPD.
The batch of 10 were melonite coated and had forward cocking serations on the slide. They also had lanyard loops on the bottom of the grip frame.
I currently am down to owning 4 examples of the 4566. None of them are TSW guns although one is a PC 45CQB and has all the features the later TSW guns had except for the idiotic tacked on rail.
The variant of the 4566 that I have shot and carried the most, as well as like the most, is the LE SPECIAL variant. Mine is decock only with spurless hammer. It has the cheesy laser etched markings on the slide. That is myvonly complaint with the gun. It shoots like a laser and is bet your life reliable. Mine has NEVER malfunctioned. NEVER. In over 8000 + rounds. And that is a casual round count estimate as it was shot 2000 rounds a year for annual qualifications and
ersonal training as well as for fun. I also shotvit in multiple IDPA matches for 3 years. Always went bang. Has a great trigger too. Smooth DA and short crisp SA let off. It looks good doing all that too. S&W still made good looking guns with nice triggers back then.
As to parts availability, bluedot has covered that. I will only say that in shooting multiple examples of 4566's for thousands of rounds for over a decade, I've not broken a sinle gun or needed a single part other than recoil springs and new magazines.
Thecconstant internet chatter about the lack of parts for the 3rd gen guns is largely due to a handful of m&p fanboys repeating it over and over on various boards in an effort to spur sales of that miserable m&p gun. In my opinion of course.
So I advise you to buy anyone of the models you have listed. Buy it, shoot it, love it. I choose the 4566 as my go to gun. There is not a 1911 on the planet, in the same price range, that is as reliable as a 4566 in my experience. And no 1911 will function as well as a 4566 with as little maintenence as a 4566 needs. Hope this helps! Good luck! Regards 18DAI
