I have used eleven productivity tools simultaneously. I have since cut that to six. The six I kept earn their cost every month. The five I cut had real capabilities that were being duplicated by tools I already had at lower combined cost.
My evaluation process: two weeks of actual use on specific deliverables, tracking time spent versus value produced. I don't evaluate features. I evaluate whether the tool moves the needle on real work in real conditions. Most don't. Some do. I report which is which.
Adam, who finds things before I do, provides a useful filter: his initial enthusiasm identifies interesting candidates. My two-week evaluation determines whether the enthusiasm was warranted. He gets one right out of approximately three. His accuracy is improving.