The money Microsoft paid mostly went to the _man-years_ of development effort towards hinting, so if Helvetica had been chosen, that would have been even more expensive.

There were several reasons not to choose the Linotype design Helvetica:

- Linotype had recently sued Microsoft for trademark infringement over the "Tms Rmn" and "Helv" pixel fonts, and that loss still stung

- Helvetica was being used by, and quite strongly associated with Microsoft's direct competitors Apple (it was a core font on the Apple Laserwriter, and even folks w/o access to those outlines would often use the quite nice pixel fonts of the various sizes of Helvetica and even more so with NeXT, since it was used as the UI font on NeXTstep (so as to better showcase their large/high resolution (for the time) screens _and_ it was part of their brand identity.

EDIT: For an example of a company cheaping out on licensing Helvetica (and Times Roman), look to Adobe, Adobe Acrobat 4 which swapped in Times New Roman PS and a matching Arial in lieu of Linotype's Times Roman and Helvetica.

My line of work often makes me share editable word processor documents with clients. I love Helvetica, but I have a strong dislike of Arial. In fact if I could choose I would use something similar to Frutiger or Myriad as a sans-serif. But when I have to prepare such documents with a sans-serif font, I always use Arial, because it looks decent enough, and everyone is almost guaranteed to have it. Nothing shiny, but a good workhorse.