I have a Big crown commander from 2000 which has the Oris 644 movt. But its Eta isn´t it? Several, a lot cheaper watches have Eta movements, especially one, I forgot the number, maybe 2614?. So for I while I felt a little tricked by the sales pitch that it was a mechanical, hence the price. I do love it though.
Why does Oris have their own names? What´s the practical difference between different movements with the same complications, say like mine and an ordinary Eta?