I'm a new XT owner, but have enjoyed Zumos 550, 660 and NAV6 for many years so found this information very helpful to spot the differences in the latest model.
Lots of subtle changes in Garmin's thinking.
Looks good though.
However, I found the same difficulties as others above trawling through the fantastic user guide on the ISSU page.
I tripped over some really good tips during my attempts to jump around the pages.
So, 30 minutes of keyboard and mouse bashing has given me a coherent 27 page pdf handbook to let me peruse at my leisure.
I think I'll pour another mug of coffee.