I think you will find them in high regard. Some get their panties in a wad about the universal long action of the rifle no matter the chambering. I can't remark on the .223 and the rifling and its suitability to certain bullets.
As to rings, some find the provided rings are perfect. others not so much. I went with Warne medium height for a 50mm scope, it uses the factory dovetail. They have been rock solid, I'm no more worried about those rings than I am about the barrel falling off.
The magazine is a pricey rascal usually found in the > $50 range, and $65 is what I generally see at the LGS. I would like a spare but have always found better use for the cash.
Mine is a 300Win Mag, I do not like the recoil, no sir, I do not like it. However, it is sighted in, now that that is over the pain is gone. It carries just fine thank you, the light weight that I loathe on the range is what I love come fall. When we go walking together, all is forgiven.
You will play hell finding a better shooting rifle than that t3.