KMail vs. Evolution vs. Thunderbird?

Deemo asks: "I use Mozilla Thunderbird on the Windows machine. Recently I installed kUbuntu, on a separate computer. Since I'm using KDE, the obvious choice is to use KMail as my default mail application. However, I tend to like Evolution's interface better, and I like Thunderbird in general from extensive use of the Windows version. I was wondering what the advantages/disadvantages are of each, and which one Slashdot users recommend for everyday use."