FWIW I just installed Big Dots on both a G19 and a S&W 629. The express style rear and BigDot front is much easier to align in comparison to a blade and notch now that age has taken away my near vision. Plenty precise enough for my meager handgun skills.
Thanks for the responses.
I ordered both (big and reg) - mainly because my wife is convinced she'll like the bigger dot more for her 43x.
I suspect I'll get a couple more of the Novak systems if neither of those perk. As was mentioned earlier – the only way to know is to find out for yourself.