I also deeply hated Brother electronic typewriters, because I could always write faster than those typewriters were able to extract data from buffer. There was always an risk that you filled the buffer up and then had a overflow. Then you had to wait until the buffer was clear so you were able to see what was lost before continuing. Really enraging. IBM Selectic typewriters were much better and a lot faster. Anyway, main point is that print timing differs between letters based on what's being printed.
Of course you were able to connect both of these to computer and use as a printer.
Good: https://en.wikipedia.org/wiki/IBM_Selectric_typewriter Bad: http://electricinnards.blogspot.fi/2013/04/brother-ax-250-el...
This should be interesting at least to tech hackers. Old but good stuff. https://en.wikipedia.org/wiki/File:Selectric.ogv