Multiple channels, auto avoidance.
I think. The FCC provides (legal) frequencies in the 24GHZ and 60GHZ bands (and other bands) for Field Sensitive Devices. I think all (most) devices have manual or auto channels to transmit on.
Thanks go to those that leak tiny bits of info. More to come when the FCC-IDs are issued and the silence period is over.
Things will get better for us as the year progresses.
I bought the Garmin, jumped with the crowd.
In stock/out of stock/in stock, oh boy got one.

Had an optical, tough to set up for prone, MagnetoSpeed that really wasn't that hard to swap from mine to the wife's.
Big bull barrel and the MS didn't seem to hurt with load development.
The wife and I shoot together, range practice, etc.
We are usually about a meter apart (barrel to barrel) and take turns shooting. Garmin between us works. Move closer to the shooter left or right.
Tried the range's LabRadar but prone at the edge of the slab and barrel muzzle was over a foot out in the grass. Not knowing operation, could not get many shots to register.
All my fault. I think most problems are user generated, even BT problems.
Falling off a bench doesn't help. Older USB connector are easy to damage, just ask my wife

The large frame (for the long range beam required) of the LR seems to be damage prone.
Those that really take care of the LR, know how to use it, gets better results.
The somewhat smaller (not much) of the other long range devices seem sturdier.
Maybe. Some seem to self-trigger off the edge of beam crossing (low strength of beam) and measure as the bullet enters the stronger section of the beam. Eliminating trigger issues would help any type made.
The Garmin also self triggers. No shock, noise, flash, vibration. Just waits for the bullet to finally get into the beam.
One thing that misleads most is Alignment. No matter what sub-transmitting mode, speed measurement comes from Doppler shift.
Beam going one direction, bullet traveling in the beam reflecting a small signal . If the bullet doesn't get into beam center you won't get long range results. If return signal comes from an angle you WILL get cosine error. The current crop of Doppler units can not determine angle for correction. That takes at least two signals or a steerable signal. Some allow you to enter an offset and hope you have it pointed down the bullet path. Narrow beam width units lose peak response with just a few degrees misalignment. Wider beam widths still capture but risk picking up a shooter in the next lane.
Current power level rules (for type approved devices) make wide beam/ long range detection sort of impossible. Our government won't let you send a strong enough signal to pick up little bullet butts at long range without making it a tiny beam with a higher power density.
When the wife and I play at the range, I photo good cherry picked groups

.
We go over the data the next day. I could have used my own SD card in the LR, but the Garmin makes it easy.
Could I have waited for something else? Why. I like Garmin but it's like last years car model.
Will satisfy me for a while.