Have a look through this forum as there are lots of experiences.

E.g. This thread discusses how the early, fully manual Hermes Ambassador is on par with the Olympia SG1: Typewriter Talk » '51 Hermes Ambassador (boardhost.com). and here, Laurenz points points out that though he likes the Olivetti Lexicon 80, it is no match at typing speed for the Olympia SG3 or Triumph Matura.

Personally, I've got both the SG1 and SG3. The SG1 is outstanding: I can type at full speed with no issues. It's got a pleasant feel (after I worked on it a bunch), and is really easy to work on. I love the look of it too.

The SG3 is very, very good, but can't quite keep up with me. Specifically: the first character after a space lands a little early, thus has a bunch of extra space between it and the rest of the word. It's interesting that the SG3 performs less well than the SG1 because they're almost identical under the hood - I even swapped parts between them while I was working on them to diagnose issues. My only guess is that this particular machine may have been well used, or the SG3, being at the end of the era of solid all-metal machines, may have been manufactured to slightly looser tolerances. It does feel looser and more clanky than the SG1. 

Thanks Rob.  I found those two links very useful.  Only wish I had gotten interested in these machines when there were still a few to be had at reasonable prices.  I'll be keeping my eye out for all of those office manuals mentioned.  I don't know that I've ever seen any of them except the SG3.

 

My daily use machine is a Royal 470. It's ugly, but boy is it a great typer. As an academic who does all but the final draft with the typewriter, it gets a lot of use. Absolutely wonderful machine. They were very popular at large newspapers in their day- and for good reason. My particular example came from Tom Furrier at Cambridge Typewriter, so is tuned to perfection. I expect it to outlast me.