I've had the ProChrono, Magnetospeed, and Labradar.
I gave the first two away.
Importantly, they all gave the same velocity ranges on the same loads. So, they're all apparently fairly accurate.
The Labbradar doesn't catch every round, especially with the smaller boat tail ones, but catches more than 50% for me. Sometimes just re-angling it works.
With the Labradar, you have to change settings between Archery, Handgun, and Rifle, which is not an issue for me. It takes a second or two to do. It takes a lot longer to reattach a Magnetospeed to a new barrel, and you have to play around with which type and number of pads keep it just the right distance from the muzzle, which is a bit of a PITA to me. Plus, the Magnetospeed changes the point of impact, which means you're wasting rounds because you can't chrono and sight-in with the same rounds. With the Labradar, you can do both at the same time. Much, much more convenient. The ProChrono was reliable, but you have to shoot through it 15 feet away, which makes it completely useless at 90% of ranges. For me, the LR is, by far, the best choice.
The LR occasionally, but rarely, picks up a round from the next lane, but that's easy to see as an error, and you just hit the trash-can button. It happened once during an 80 minute sessions a few days ago.
