2017 FJ here.
Originally I had some stability issues. At the 1st service (ca. 600 miles) they adjusted the suspension.
Now it is almost gone.
Then, back in July, I took a 2018 Tracer for a spin (back in Europe). What a different machine! No stability issues. I rode it at 200+ km/h on an autobahn. No problems at all. And the suspension was set to quite soft (I guess - I am heavy - 195 lbs - European riders are lighter, I guess, so the suspension was set to their average weight).
Sincerely considering an upgrade to 2019/20 Tracer (non-GT) after one more year.