Best optic for Ruger 22/45?

The only pistol I shoot regularly that does not have a red dot on it is my 22, a Ruger bull barrel with a Volquartsen trigger setup.
I am happy with the trigger, but am thinking I might be introducing complexity by the 22 being the only pistol without an optic.
I see here mentions of Ultra dot which I have zero knowledge of.  Suggestions?

Any of the tube type Ultra-Dots are good. You will see a lot of them on the line.

Aimpoint Micro is probably the next most popular. Several of the AP Micro knock-offs are pretty good (Holosun, Primary Arms, Sig). I would not recommend any of knock-off that sell for $100 and lower.

Aimpoint 9000's are not uncommon.

Very few of the open holographic sights have click adjustments. That may be OK for a 22, but is not repeatable enough if you need to adjust your sights between distances and ranges.

Best = Aimpoint, but not necessary for 22lr pistol. It is a "micro" red dot, which means shorter tube, but still a tube. 
Sig Romeo 5, 4 and Holosun 4 and 5 series will do just as well at half the cost and also micro dots. 
Vortex Crossfire and Primary Atms could do the same even cheaper at around $99, but I see prices may have gone up.
Bushnell Trophy TRS25 is still one of the cheapest micros that does the same for 22lr at about $75 or lower. Many people ding on it, but Ilove mine. Totally adequate. I know people using it on AK's and no issues. 

Ultradot gets you a long tube optic, which makes it easier to acquire. They are some of the best and commonly used long tube optics. 
Sightron and Millett can be found cheaper on secondary market and are made in Japan. 
Tasco Pro Point is adequate as well, can be found dirt cheap on secondary market. I had Tasco on 38 Super and did not miss a beat. Nice round dot and long tube.

This is the Tasco variant I was talking about. 50 bucks, made in Japan and all. YMMV, but worked very well for me.
https://www.ebay.com/itm/284936405366?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=bH3R5NLbSIm&sssrc=2349624&ssuid=aot_XzqsR0W&var=&widget_ver=artemis&media=COPY