Sarah has created a masterpiece with her 9000. I've seen and heard it run and it's magnificent. I don't possess Sarah's abilities so my 9000 will remain stock. Even the prototype hung over on yard curves and turnouts, so we can't expect the model to do any better.
I may pick up a Sunset 9000 and rework it. I had one when I got the KOH's and sold it...should have kept it.