I started out thinking that I didn't need a red-dot on any of my pistols. I liked shooting with irons, and I was pretty good at it. It felt like driving a manual transmission car.
Then I tried one.
I'm faster, and far more precise now with a red-dot than with irons. I still get regular reps in with my carry pistol that doesn't have one, so it's not that I practice more with one. At first I had a hard time finding the dot and would have to find my irons first, then the dot, but a little bit of practice took care of that. There are also some that have reticles with a circle + dot that makes it easier to find if that's a concern.
If the added bulk isn't prohibitive to carrying, then I would absolutely recommend trying one out. The only reason that my shield plus doesn't have one is because it doesn't have an optic cut, and I can't decide if I want to have the slide milled, or look for another carry option.