This at a time when printing from, for example, a non-WYSIWYG WordPerfect document on a a PC would print your entire doc in whatever printer font you had installed and selected. Seems crazy now, but printing to an ImageWriter from a Mac was a huge step up, poor DPI notwithstanding.
Yeah, I used one back in school. It had a 'letter quality' mode which looked like a million bucks compared to the typical Epson monospaced dot-matrix printout. Probably subtly nudged up my GPA.
The Imagewriter had twice the DPI of the Mac screen so I don't think they were overselling it. WYSIWYG was a big deal at the time and it did what it said.
Remember this is a time when macs still did not display vector fonts (Adobe Type Manager just came out in 1989 and was not free) and of course there was no antialiasing because it was a 1 bit display.
Did they ever use one of those things? I feel the urge to laugh uncontrollably.