I've had two range trips with the BOLD sights on my G19. The first trip was kind of a wash. I was at an indoor range with guys shooting ARs on each side of me (lucky me). I shot low most of the trip but I can't blame the sights. I also shot like crap with the Trijicon HDs that I have had on my G26 for a while. On the 2nd trip things were much better. I really like the slimmer front site compared to the HDs for accuracy. I'm still getting used to the width of the rear notch. The original HDs have a .25 difference where the Ameriglo BOLD set is .40 (.125 front and .165 rear).
One thing that may be useful for other folks is that these Ameriglo BOLD sights are .035" taller than the usual Ameriglo sights. From what I can tell on their website, Ameriglo typically has a .165 tall front and .256 tall rear for most of their sight sets. I believe those heights match up with the stock sight heights for Glock. I was going to order a set of the regular Operator rear sights that have a .150" rear notch to try with the .125 front of the BOLD series, but realized it was taller than the stock front sight. I ran across an Instagram post from Ameriglo on the new BOLD sights and they confirmed they are .035" taller. I'm not sure why they decided to make these different heights than their usual sights. It would have been nice to be able to try out some of their other rears easily. They did mention in that same Instagram post that they have .125 ProGlo fronts in several heights available if you call them so I guess that is an option if you want to try a different existing rear.