Hey OP, if you haven't already made your decision, post your question on a Jeep forum (Wranglerforum is a good one). You'll get better (and experienced based advice) there.
Most of the comments regarding 4lo and JK Rubicons in this thread are not correct. The only difference between a 4Lo for a JK Sport and JK Rubi is the top speed - and if you're driving in a responsible manner, it won't matter too too much.
In the steeper sections and more technical areas, you'll appreciate the deeper 4Lo of the JK Rubi case - especially if you have a manual. I use 4Lo all the time. If traveling in groups of sports & Rubis, people use different gears.
I use my rear locker in 2hi, 4hi, and 4lo as do many of the folks. So again, the comments about 4lo/lockers only are not correct and their experiences are far from universal.
The Rubi gives you stronger axles, factory lockers and electronic swaybar disconnect. There are some differences in the diff (limited slip vs open), but that varies with the options. Everything else is the same. A Rubi can be equipped the same as a Sahara or it can be pretty basic.
All 4dr Jeeps have payload of 800 to 1000lbs or so (this includes passengers). The payload sticker on the door is based on the stock configuration (soft vs hard top, dual tops, etc) - so plan on doing some math (add/subtract) based on your final configuration for the Ursa Minor.
Depending on your perspective, 800-1000# may sound like a lot or a little, but many many 4drs run heavy and have many trouble free miles. The JK/JL platform is very very tough and well proven.
Regardless of the Jeep you choose, an Ursa Minor plus the usual camping gear, you will be running heavy - and - while the factory suspension is capable of handling the load, it won't be very comfortable (lots of sway/wallow)
Stiffer springs and better shocks will do you good. There aren't many companies that offer stiffer springs at stock height, that is why many get a small lift (2") or so. If you go this route, do not get the Mopar Lift - it is too soft.
Regarding the manual :
The issues with the TOB bearings vary - mine has been noisey since I bought it - but at 135k, I'm still on my stock clutch and bearing assembly. I also have a 3.8 and it is a 2007. I tow heavy all the time in the back country or locally.
If you believe the forums, my Jeep is a POS...but in actuality, it has been a very reliable tool. The clutch/TOB issues arent that bad - very similar to people talking about the 3.8L motor - tons of of over-reacting and lots of fear mongering typical of forums.
I've owned a manual JKU Rubi for over 10 years..I drive it hard, but I don't abuse it (drive like an idiot.)
I have owned/driven many 4x's - I've never not liked/been bothered my the 4:1 ratio of the Rubi.
My work takes me many places, including the back country and travel extensively with an empty or heavily loaded Jeep. It has been a very reliable vehicle (for how it gets used) and the maintenance costs have been very low.
