Lots of good input on this. I have wheeled the mortal soul out of mine and back in the last 3 years and it's a tossup, cliched as it is to say. It really depends so much on what type of terrain you're in. In terms of trail crawling it's ok. It's a pain but just fine if you're really good about not slipping the clutch. But you will have to ride it sometimes. I did one ridiculous trail that's really a sxs trail now, because that's what they do to trails, and it was a double whammy: my gears were just a little too high for the conditions so I did a bunch more spinning than the gx I was with. Steep, bouldery, and shale. I had to be pretty violent to get over some obstacles (unlocked, non OR gearing, 32" tires). THEN, the worst part, on the way down my idling speed in 1LO was still about twice as fast as the JK in the front of our group. So for like 3 hours I had to clutch in, roll 200 ft, clutch out and wait for space, and repeat. On flat dirt. I even stopped to wizz and get some space ahead of me and have a cigarette and the twits came back to find me after 90 seconds. Like I was going to get lost on a trail 20 miles long with no forks. It was a fun day, but absolutely brutal. I felt like I had a kidney stone and a torn meniscus by the time I got home from the clutching. But the vehicle worked. Keep in mind that was a trail with about 7000 ft elevation gain.
Slickrock obstacles haven't been an issue. You just need to be confident, act like you've been there before and punch it.
All that said, having the direct power of the manual has absolutely been a benefit in saving my butt on other types of trails, and it's a lot of fun even if you're not in trouble. I took a wrong trail recently and found myself in a really tight mooondust/baby powder track. I found a place to turn around and knew I needed to murder my way out since the dunes were steeper and more uphill. I'm not sure I'd have made it out in an auto without a lot more power. It was really dumb of me since it was well over 100 and several miles from even gravel. But I just matted it in low 3rd and rode a tiny bit of air and made it out.
It's fabulous in mud, absolute joy.
Not having to worry about transmission cooling in a hot state is really nice.
Bottom line: don't pass over one because it's a manual. Don't avoid wheeling it if it's what you have. But it does have some medium benefits and real drawbacks.