That is a good question.
I thought about it for a while, and had to do a side by side comparison.
They really are surprisingly similar. My LCR is a very early .38 with the laser grip.
In slow deliberate fire, the LCR feels more springy, a little stiffer, and has a little a little take-up before the first "click" as the cylinder starts to rotate. It's bigger grip frame probably offsets any perceptible disadvantage.
The Rohrbaugh is more consistent in that it doesn't seem to stack up or lighten through the trigger stroke. Buttery and direct is the best I can come up with. My LCR definitely has the smoothest trigger of any small frame revolver in my experience, but is not in league with my pup.
All that being said, neither one is a finger tip, ride the trigger, feel the break, long distance target gun in my opinion. When I shoot either of these pocket rockets, I grip it tight and pull straight through to the trigger stop, and then let the trigger all the way out. When squeezing them off in real life, my booger hook doesn't feel much difference.
I like the LCR a lot and pocket carry it when I am going to be in an environment that is unfriendly to the Rohrbaugh's finish. I take special care of my favorite, and bring out one of my yard dogs for the dirty jobs.
Hope this helps.