I set about testing various radar chronographs this summer, still working on much of this, due to work and coaching schedules and interfering extreme frequency rainstorms.
Much of my data I have already published is out there on THR and the Hide, I'm happy to copy it over here in threads if there is interest.
Personal Opinions & Experimental Observations:
Caldwell VelociRadar:
Personally, I hate the Caldwell. It’s essentially a clone of the LabRadar V1, and it costs as much as the Garmin Xero C1 or LabRadar LX, but it’s a MASSIVE wind sail, and seems to have nearly all of the same issues for aiming as we experienced with the LabRadar V1. If it were priced at $300-350 with the new price of the LabRadar V1, Athlon Rangecraft Velocity Pro, or Magnetospeed V3, I might be more forgiving, and I’d still likely recommend the Athlon Rangecraft Velocity Pro over the VelociRadar. Acoustic trigger instead of radar, so it hides interference until it’s too late. The multivelocity and BC calculation function is too short of range to be useful for long range shooting, like, where BC matters, so that's a null function for me - no value. Aiming is a pain, displacement by wind or brake blast is a pain. Hauling it around is a pain, and the screen is tiny with buttons almost as big as the screen... The button and screen layout kinda remind me of fisher price toddler toys. They missed the boat there - I feel like they designed it to compete with the LabRadar V1, then the project stalled for too long, the Garmin, LR LX, and Athlon all came to market, and Caldwell didn't turn the boat, they just launched an outdated, underperforming product at a ridiculous price point. It has to be cheaper than an Athlon by $100 before I'd be interested.
LabRadar LX:
Great unit. Heavier and bulkier than Garmin, same price, which means it’s a little less apt to get blown over by brake blast, but also means a little heftier and maybe heavier than some guys might want mounted on their rifle. Far better app integration than Garmin or Athlon. A little more frustrating that it has to be armed and little more frustrating to operate due to the acoustic trigger vs. radar trigger, but overall, an awesome bit of kit. Screen size is smaller than the Athlon or Garmin, which kind of sucks for eyes 40yoa and older, but you also can display live to your phone, so that's kind of a wash.
Athlon Rangecraft Velocity Pro:
Light and small, nearly identical operation (down to the HMI screens) to the Garmin. I actually don’t like that it has extra buttons, at least don’t like that the buttons are on the side AND on top, as I end up blocking my view of the screen with my hand, and have to change position to press top then side buttons back and forth, and more often end up knocking the Athlon over on the tripod, and I have to make sure it's not positioned so close on my rifle mount that I can't press the side buttons. I've described, in detail, some of the issues I have had with data syncing (rather, failing to sync) to the app, velocity offsets compared to known velocities and results from other units, as well as the relative disagreement between two Athlons from one shot to the next, compared to the consistency between units for the other brands. I'm confident in stating my 2 current Athlons are not reading within the specified +/-0.1% of claimed precision, for the simple acknowledgement that typically the AVERAGE difference between the two units is greater than 0.2%, and typically maxes out around +/-0.5%. Still as good or better than any of the optical units on the market at lower prices, but not as good as I'm seeing from the Garmin. Aiming is easy, start up is easy, size is great. Just some bugs to workout. These are Radar triggered, which I believe is the best method, however, they are single channel transceivers, so unlike the Garmin which can detect interference and warn the user to restart, which kicks it into a channel scan for free channel, or the LabRadars which can have the channel manually changed to dodge interference, the Athlons can't move, so they're stuck moving physically away from interference. I do think the offset issue will improve with firmware updates, the sync issues have been already resolved for almost all iOS users, still working on the Samsung/Android users, but I'm not 100% sure why I so consistently see the wider band of disparity between two Athlon chrono readings - but again, +/-0.5% is still tighter than the optical chronographs out there, and in general, will deliver data which is close enough to truth for anything we're doing (except POTENTIALLY ELR shooters). For me, the lower price point aligns suitably to this slightly looser precision performance, and everything else is VERY similar for the Athlon and Garmin (I guess the Athlon app has more features and functions for additional hardware, like ballistic solver and thermal scopes, but none of it is very intuitive). I'd buy the Athlon over the LabRadar V1 eight days per week.
Garmin Xero C1 Pro:
I have had my Garmin longer (naturally) than the other units, save the LabRadar V1. The Garmin established a new standard for user-friendliness, and it delivers top marks in all aspects against the other units EXCEPT for the app integration - the LabRadar CONTROL in the app isa big benefit in my view. The Garmins have been the ONLY of the 3 brands I have tested which could potentially be delivering against their promised specification of +/-0.1% precision, as the two units ALMOST ALWAYS read within 0.1% or less of one another, and in only one of my tests (30-100 rounds per test) have they been outside 0.2% spread from one another. (LabRadar LX's have been very close, but just outside of that promised specification). They're lightweight so occasionally, brake blast on our ELR rifles will knock them over on the tripod (Athlon tripod is heavier, I haven't knocked one over yet, but also haven't used them as much for my 375 Cheytac). Quick, easy, reliable.
Performance wise, the LabRadar LX and the Garmin Xero C1 are nearly neck & neck, with a slight, consistent edge for the Garmin on data consistency. A guy has to pick whether they want a lighter unit with the Garmin or the app control with the LabRadar LX. The Athlon is priced lower than these two, accordingly with precision performance, and for many users, the Athlon will do what they need (doing it better than optical chronographs, and as good as the MagnetoSpeed V3 or Sporter). I wouldn't touch the Caldwell VelociRadar for their street price, would rather have the LabRadar V1 for less money which does the same thing, personally rather have the Magnetospeed V3 at that price, and honestly, much rather have the Athlon than either. But removing the price hurdle, the Garmin and the LabRadar LX are worth the extra price to me.