-A stock H3 can offroad any trails that a stock Wrangler can, and is often more capable than the Wrangler unless it is a Rubicon model.

-A base H3 is more capable than a base Wrangler due to the Wrangler having open diffs with no traction control and a very weak front axle.

-Both the Jeep Rubicon and Hummer H3 Adventure were designed and spec'd to be able to navigate the Rubicon Trail in stock form and both were taken across the trail after development by their respective engineering teams with no issues.

-Add 35" tires to a Wrangler and you'll likely blow up the front end with any aggressive offroading. Plus the factory Wrangler brakes are barely able to handle stopping 35's like an H3 can.

-I've owned both a Rubicon and an H3. Both have exceeded my expectations off-road. In on-pavement winter driving conditions, the H3 is the hands down winner.


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Just to add a bit of Jeep fandom - a couple points not yet mentioned. A Wrangler has better visibility. The H3 isn't as bad as some articles make it out to be, but the Wrangler gets a clear nod on this one. Also, you can take the top off a Wrangler. Perfect weather, top down, half doors off, bikini top on for shade - that's about the only thing I miss about the Wranglers I've had in the past.

 

I would not buy a Yota if it was the last vehicle on all the car lots for sale. Two words: Frame cracker.

 

We have both a Wrangler Unlimited and the H3. Both will be more than adequate for the kind of offroading you describe so the choice is more about which you like better. For my money the H3 is more comfortable by a bunch but lacks some of the fun of driving topless, doorless, etc. Turns out the Wrangler also has a larger cargo capacity - doesn't look like it but it's a fact. Aftermarket has a lot more toys available for the Wrangler than the H3.

Bottom line is if you want a vehicle to get you comfortably to offroad locations, you can't beat the H3 - and I have found the I5 3.7 adequate in power if less than exciting. If you want a vehicle primarily for fun driving offroad and don't mind a bit more noise and a less comfortable ride getting there, I'd pick the Jeep. Better yet, one of each!

 

We narrowed it down to a 2009 Wrangler and the 2007 H3. We test drove the Wrangler first. Immediately we noticed how hard the seats were and how uncomfortable they were. I've had jeeps my whole life, but I just couldn't believe how uncomfortable the seats were. Then immediately upon sitting in the hummer my fiancee and I both commented on how comfortable the seats were. We liked the interior a lot better in the Hummer too. Comfort is a huge thing for us as my fiancee suffers from Rheumatoid Arthritis. That wasn't the only reason we chose the Hummer, but it was important to us. I love jeeps too. but I'm so glad we got our Hummer

 

I've owned many Jeeps, C7, YJ, tons of TJ's stock, mild lift, and wild lift.. Of all the jeeps my 2000 Sahara TJ on 33's was the best of both worlds, good offroad, and onroad. On the street, the jeep was rough ride, bouncy (short wheel base), and the RWD sucked in snow/rain and even on the street kept it in 4wd on really crappy winter days.
I just got a 07 H3... It's hands down a better vehicle. Looks great, very comphy, the wife will ride with me, my 8yr old doesn't have to climb on my seat to get in the back, 4wd is awesome. The 3.7l is a little slow as others have said. My H3 has a standard transmission so it helps a little and I feel like I have full control of the vehicle.
Coming from a huge Jeep fan, I've been called a jeep trader by my friends for getting the hummer, but after they take it for a spin, I find a few of them looking for one as well.
MPG in the H3 is about the same as my jeep.. If not a little better.

 

I love the H3, 220hp and all....this is coming from an owner of a 400HP camaro SS if that says anything.

 

My wife and I have two, 2007 H3X and 2008 Alpha , the 3.7 is just fine unless your pulling something heavy. MPG? the 3.7 gets about 16 city 20 hwy, the Alpha gets 14city 17hwy, I've also owned a lots jeeps. If your looking for something that rides great, turns sharp and looks like nothing else on the road buy the Hummer.. If you want something that's no better on gas, rides really bad and won't go past a Dodge dealership w/o pulling in for parts, buy the Jeep. Plus here in NC mountains the HUMMER's are holding more value than Jeep's, maybe because their getting hard to find and every street corner has a Jeep for sale. If I was looking to buy one to just play off road i'd buy the 3.7 (Cheaper) and will go just fine off road. If you're going to pull a boat / atv's / trailer I'd buy the Alpha.