I noticed a huge difference in comfort with the transition. I went from vittora pro slick I think to GP4000 25mm, it's possible tire quality might be due to the perceived difference.
With a bigger tire, you can ride at lower pressure and further increase the comfort. I used to ride at 100-110 23mm now I do 90-100 and it feels so smooth. In fact, I will never go back to 23mm.