GK, I have an old one that is a little smaller than that model. Mine is a 16x20 and I think it was made in the 90s. I had a lot of trouble with the bearings going out and the blades breaking, and it was always hard work to fix it. I decided to replace it 6 years ago and looked at every brand I could.
A dealer just a few miles from my house had an Atlas available, but the blades on it were really thin. I probably would have bought it if he would have changed the blades out, but he wouldn't do it. I decided that either Brown or Tuffline would be the best way to go, and went with Tuffline because I was able to get a great deal from RareBreed and he even delivered it. It had been a much better disc than the Atlas. It has a different type bearing and the frame seems stronger. I did get them to change it at the factory to heavier blades than what was standard; it seems they all try to get by with lighter blades than they could. I have had one blade to break since I've had it, and I broke 2 or 3 every year with the Atlas.
Here is the model I bought:
https://monroetufline.com/shop/agriculture/tl43-series-tandem-disc/This is a lighter disc than what you are wanting, so not an apples to apples comparison. However, I was comparing similar discs when I was looking at them in 2012, and I didn't think the Atlas equipment measured up to Brown or Tuffline. My info could be out of date by now, but maybe it helps you a little. Good luck deciding.
BTW, the 16x20 Tuffline that I have with the heavier blades weighs a little over 1200 lbs. It is ALL that my 5075 will pull in sandy soil. Never had any trouble pulling the similar sized Atlas.