Have owned a M35 since the early 90's and a Labradar for almost two years. I ran them together and calculated the difference in distance from the muzzle a half dozen times and they agreed within single digits all but a few shots out of several hundred rounds.
If I'm headed to the range I almost always plan on using the Labradar because there's no need to step beyond the firing line for setup--and setup is quick once you learn the nuances. I also use it when shooting from prone when I want to chrono a load. And recently it worked in low teens temps when cold weather testing--I was skeptical it was going to work. I did bring it into the cab of the truck with me each time I got in to warm up!
