I refuse to vote without context. I prefer serifs on large amounts of text (books, newspapers, content portion of websites, etc.), but I prefer san-serif on headings and the like where where's only a small amount of text (I'd count ClearviewHwy in this, but the lower case 'l' clearly has a serif).
And speaking of 'l', for passwords and commands to be typed in -- I prefer serifs because I can better differentiate between 1/l/I ... but I need to use something like ProFont so I can better differentiate between 0/O.