IMO, it totally depends on your genre, and your drum sound objectives. I use GA, Battery 3, (Battery 4 is a joke due to features left out by NI) most Toontrack EZX extensions, and SD3. Part of the cost of SD3 was paying George Massenburg for his work involving the SD3 library. It sounds superb, but whether or not you need what he contributed is another question.
Comparing GA, Battery etc with SD3 is like comparing apples to oranges. Not so much the sound, but the tools available such as tap to find, sound details and flexibility. For example, if you want the most realistic acoustic 70s drum kit available, with adjustable mic bleed, then SD3 with Custom & Vintage. But if you are doing a pop or EDM record you may not need to consider mic bleed.
If you are looking for a sound that you haven’t found in GA, then certainly try something else. But it’s quite silly to use something else if you think GA sounds great based on what others tell you.