When I first started shooting handguns, I tried a set of XS Big Dots on my Mother In Law's Glock 26. At first, I really hated them, because, especially at longer ranges, they weren't particularly accurate. With a G26 and standard sights, I got tighter groups at greater than 15 yards. Once I started learning more, and realizing that an inch or two at 25 yards isn't a huge deal, I realized how much I liked them. I don't have a set currently, but am seriously looking at getting some soon. They are so fast. You mention how you might not use the sights if it's a quick draw type situation, but unless you're shooting from some kind of compressed or retention position, your sights will be in front of you, and that big dot is so easy to pick up.
See if you can find a gun with them you can shoot. I wish I had gotten them when I was looking at replacing my sights originally. As soon as I can justify it, I'll probably look at getting a set. They're just so fast and quick to pick up.