Hummer's are much cheaper to own/operate vs a Jeep or Land Rover.
First my Jeep was always having issues and my Auto Zone rewards were always nice, however it got old having to baby something so much in fear of it dying on ya. Both my 05 Wranglers were nothing like their Trail Rated badges... Brake Caliper's seemed to love locking up at any given time, transmission PCM liked limp home mode, blower resistors went out whenever they wanted to, and the flexplate might as well have been made out of an aluminum pie pan.... Now my 04 Grand Cherokee was bullet proof, but parts weren't all that cheap for it if they did go out. Land Rover's aren't great on gas with worse than H3 ratings and they require 93 Octane fuel, not to mention parts are hard to find unless you go to the dealer or thru an online Rover Retailer.
I've owned my Alpha for 2 years, and my Adventure for almost a year. During that time I've only had to replace small items that didn't cost me an arm and a leg. The 3.7L gets much better MPG that my lifted WJ or Wranglers. My Alpha is about on par with my lifted Wranglers on MPG, but it's miles ahead in comfort, ride, and quality.
I've been able to cross-reference a lot of H3 Parts onto other GM vehicles, and the parts are much cheaper vs Jeep or Rover. A TJ/LJ non powered mirror from the dealer was 175.00 each, and JK powered mirrors are 200.00 each easy. It just depends on the part, but most H3 parts you can either find used online or cheaper from online retailers vs the dealership. That's about true with any car company and buying parts.