NAV beacon's had a deffinate purpose prior to the introduction of the ADS. The basic difference is, if one is just passing through a system in route to another, then honking the ADS gather's data which can be utilized by both the player if needed, and then sold for a nice little sum. While scnning the NAV beacon use to be the only way to aquire data, the ADS does it faster. HOWEVER: An ADS though will generally only include a few objects spelled out entirely, and the rest will be listed as Unknowing objects. Scanning a NAV beacon will give on a more spelled out list of the various objects in a system. Thus if I'm just passing through, I only honk using my ADS. If I have offical bussiness in a system, I'll honk and scan the beacon. Becasue though I can with experince determine the data from the ADS, the data from the NAV beacon is more discriptive. Thus the NAV beacon thought slightly antiquated, still has a valuable place in the game. And as any body who's ever gone outside the bubble can attest, NAV beacons are only in occupied space. And even then, they are not in every single system in the bubble. I've personally, come accross a system or two, that didn't have one. And outside the bubble, there isn't any.