I have 40mm (700c) and 60mm (650b) Schwalbe G-one tires
My favorite is 40mm. Light, agile, and fast.
But if you aren’t interested in speed/weight/hill climbing, 60mm is so super cush. You might like it better. My speed dropped from 15mph to 12mph average, but that was probably because the fat tires are on a slower bike. For my specific tires, the 38mm are not going to roll any faster, but are a bit lighter
(I think on the same bike there would be less of a time/speed difference, besides the 60mm tires seem to be a little faster on a flat rail-trail type course where bike/weight makes little difference).
Certainly the 60mm is nowhere near as agile, but that is an advantage for some people/routes