Netscape was one of THE original browsers - long before Opera, Firefox and all those other "new" ones.
It WAS very good and many considered it better than IE but then it seemed to lose its way and while IE ran ahead with all sorts of new innovations, Netscape sat there bathing in past glories. There have been several attempts to reinvigorate it and perhaps now is the time for its renaissance.
We use it for browser checking in web development but not as a general purpose browser.
Regarding safety, it probably is safe at the moment as the malware writers are very egotistical and aren't going to concern themselves with little-used software to show off their supposed talents.