When you are transcribing a Yngwie Malmsteen solo or a Dream Theater odd-time riff, you cannot afford lag or mouse-hunting.
Later versions (6, 7, 8) introduced RSE 2.0 and 3.0. On paper, they are superior. They have larger samples, more round-robin cycles, and better amp simulators. So why do pros stick with 5.2? Guitar Pro 5.2 with RSE