Please modify the font for displaying authentication banners to some fixed width font and increase the number of columns to 80 characters. I also recommend at least 24 characters for the number of lines.
Authentication banners are often some kind of ASCII arts which propagate an identity and most common information about the host which may be useful before logging in.
Many authentication banners look ugly when displayed with variable with font. I assume that all banners are fairly pretty if displayed using fixed width font.
I believe there would be no drawback because of this feature.
Sorry for my bad English.
Darabos, Edvárd Konrád
WinSCP 4.3.2 (build 1201)
Windows 7 (Version 6.1 build 7600, 32 bit)