I used to have an Elna 9000 that I got in 1999 from a dealer (probably a trade-in). That summer I was both semi-nomadic and did a lot of wedding sewing, and it was perfect for that...compact machine, lots of pretty stitches. But I could not get it to do a successful buttonhole except by using the old mechanical buttonholer my mom had for her Elnas because the 9000 electronics were off very slightly.
The big selling point for the 9000 was that it was the last Elna made in Switzerland but mine felt like it was produced as they were packing up the factory ('let me just solder one more thing!").
I believe the 8000 was slightly more...stable.