They feel very different than a Selectric I/II, but the Selectric III uses a similar keyboard action. A manual typewriter feels very very different (and is impossible for me to use, as someone who is a key pounder at times - like my cube mates could tell when I was writing an angry email by how my keyboard sounded, lol)
At the time I thought it was made to appeal to the tastes is mechanical typewriter users who were still very common in those days. I just had a cheap BTC foam-foil one which was really nice actually but did need a full take-apart and clean every year or so. But the touchwas so much lighter than the model Ms at my dad's work.