The 8900 has the accufeed system so you don't need a walking foot. The change from the 7700 (which I have to) the 8900 is that the throat plate is a quick release and it has separate single hole and zigzag plates. Also, the forks for the accufeed don't interfere with changing feet, etc. I believe the Elna 760 is the sister machine to the Janome 8900.
I know the older Pfaffs (pre 2000) are good, but I had one in 2003 and the bottom tension was a mess -- there was no way to sew a zigzag stitch without the back being laddered. It spent 2 months in repair, then the shop gave me a new machine that had the same issue. I haven't tried Pfaff since.