In Friday I did a 75 mile ride on my flat bar hybrid on a MUP. I'm planning on doing a century over the 4th of July weekend on the same MUP and the same bike. I will say this, after 75 miles my hands ached but there is more than one hand position and things you can do to mitigate hand pain.
Allow me to say this, first I'm only doing this one time and it's simply to say I did it and second it will be my first century except I did one on a fluid trainer using Zwift a few months ago. Besides the 75 mile ride I did this week, I completed four (4) metric centuries in May on this bike and i plan on doing at least 10 more metric centuries on this bike/trail this season. I'm fyi 62 yrs old. I don't think I would use this bike to do a century on the road.