I went from 2.7 megapixels, to 6 megapixels, then to 8.2 megapixels, then to 12.2 megapixels, all on APS-C.
My first full frame camera was the 12.8 megapixel Canon 5D, commonly called the 5D classic. I used that for several years, then in 2012 I bought myself a used Nikon D3X, which was a 24 megapixel full frame.
I was extremely happy with the image quality from a 24 megapixel full frame, but two years ago I bought a Nikon D610, which used a second-generation 24 million pixel full frame sensor. The image quality even at elevated ISO
levels was very good, and about a year later I bought myself a used Nikon D800. I was extremely astounded at the difference between 24 megapixels and 36 megapixels. The noise level between the two sensors was extremely close, and I think that the 36 million pixel full frame sensor is every bit as good as medium format film used to be in the 1980s. 36 million pixels offered me an incredible ability to crop images at the computer, with almost no visible loss of quality. Compared to 18 years ago with a 2.7 million pixel digital image, the degree of crop-ability is simply staggering. Compared to 12.2 million pixels 36 million pixels offered me an incredible degree of freedom to crop.
I think that 32.5 megapixels will really be a huge step upward to people who are used to 16 and 18 and 22 megapixels or less.