I could probably use glasses for distance. My once hawk-like vision has deteriorated and I am afflicted with the vitreous detachment that is common as we age (ie: dark "floaters").

But I can still aim quite well and do good in steel plate matches I regularly attend. I used to be able to see 9mm hits on a black target at 50' but now I need binocs or a scope or a splatter target. Forget seeing .22 at that range!
The pistols shown are my "competition" guns although perfectly fine for carry as the triggers are not THAT light

(3.5lbs). The red dot sight (RDS) is a Holosun 507C and the sights are Trijicon. The RDS is on a Dagger SW1 slide with comp and I put a white square dot (nail polish) on the tall front sight that came with the slide so it is easier to pickup the dot. I think it is a 3MOA dot--some prefer a bigger dot, say 6MOA. The 507 is also 32MOA circle or circle/dot. I prefer just the dot.
For "iron" sights (they are steel) the Trijicons are nice because of the "U" notch in the rear and yellow outline on the tritium in front. At arm's length, the yellow fills in the U perfectly.

That is a Gen4 Glock 22 slide with 9mm conversion barrel. Both guns are Lone Wolf frames.
A properly sighted RDS is a wonderful thing!

BUT keep in mind a gun sighted for you may aim differently for someone else. Or for your non-dominant eye so be sure to check with both. Neither a RDS OR irons will correct bad aim or flinching or anything like that. A common complaint with RDS is "flaring" and is usually caused by the sight being too bright but can also be caused by uneven curvature of the lens of your eyes (astigmatism). Budget optics can often have flaring issues--you get what you pay for but I have a $80 TruGlo on my SIG P322 that works fine.
