I have a Chrony Beta, Magnetospeed and Labradar.
I used the Chrony Beta for 20-25 years. It is a PITA to set up, especially since it is so far in front of the muzzle. Ambient lighting makes it kinda finicky too... but , I will say once it's set up properly, I can count on one hand the number of times it gave an erroneous reading or didn't pick up the projectile. Can't attest to extreme accuracy as I did not compare it to another unit more than a couple of times.
The Magneto Speed was my second chronograph. I found it accurate, once set up I got reliable data. My issue with it is it is also a PITA to secure to a barrel and KEEP it secure. I don't care how tight you secure the fabric strap on a magnum barrel, between the heat and recoil you had better check it every 2-3 rounds.
I also found that the weight hanging on the end of the muzzle not only affected my POI but also changed my group size. Had someone on here make the comment that it could not change group size. Wait one, isn't that exactly what a harmonic balancer does?? The problem was it made my groups smaller on my main rifle, when I removed it, the groups opened up 1". The spacing is critical enough that I would miss the occasional shot. Another con is when switching between rifles, different size muzzles and suppressor diameters there were not enough combinations of spacers to get an exact fit.
I got frustrated with that enough I bought the Labradar. A gunsmith I was talking to from this site told me it was a complete game changer. I really like it, easy to set up and use, the only problem I've had so far is the unit picking up muzzle blast from other shooters in close proximity. Admittedly, it was my fault not having it set right for muzzle blast sensitivity.
This far along, I am extremely satisfied with the Labradar, have not used the Magneto Speed since...
just my .02