"Experts"

[JMT3]

First up my rules are that fit is the most important thing if you want to go fast. If your fit is correct then you are comfortable and can push your bike fast and sustain it.

2nd I too at 6 foot tall went to 165’s and like it. I converted all my bikes and went shorter on the gravel and mtb but 170mm.

I like my 5000S at 25mm which when I measure with my calipers and once stretched are really 27mm. Never went wider on the road and don’t plan to unless I am not comfortable. Do ride 83 psi front and 79 psi rear. Lower pressure definitely helps.