1) Do you know what it is?
YES
2) Do you have it?
NO
3) Would you buy/fit it?
NO
4) If so, why, if not, why not.
Because I am against portable stuff in the cockpit.
I am doing an exception only with the Garmin296 as a back up GPS / VFR advisory moving map and I use it only with its battery to avoid loose cables in the cockpit.
Also I believe these devices are not accurate enough.
For traffic awareness you need a device that shows you relative bearing and altitude with accuracy so you know where to look for instantly.