No, I vastly prefer the mobile site on my phone.
width: 100%; // Fixes white borders (browser default table width is normally something like 85%)
max-width: 750px; // Keeps columns from getting overly wide on desktopI do it because I think it maps better to text widths, which is what you ultimately want to prevent getting overly wide. It also handles different font sizes fine, making the site still accessible for people with big system-wide fonts.
I'd like to know, is there a downside to em or a reason to use px instead?