You may have your favorite paper/ patent / project, which you think is your best. I do have such a paper, it is attached. I started to think about this problem at age 30, obtained the solution at age 73. So, I worked on the problem, on and off, for 43 years. This paper is most downloaded between all my papers by RG peers, so, they confirm my own opinion. But that is only my personal experience, other people may have different opinion in rating their own works.