2018 Gs350 fsport here. I'm getting this notchy inconsistent brake pedal feel when I press the brake pedal. It's most noticeable when brake hold is turned on. I can understand why it feels that way with brake hold on but even with it off it still doesn't feel right.
It's like a small bump when you initially step on the brake. It doesn't feel smooth. After that it feels fine as you press the brake further. It's worse when brake hold is on.

 

No such symptom on my 18. You need to hit the dealer.

 

the only thing I've had with my 16 GS F-Sport with the brakes is if I wash the car can and let that lite rust buildup stay on the brakes for a few days it caused pulsation in my brakes. few hard stops smoothed it right out so now after a wash I always take it for a quick ride around the block clean off the rotors