It really depends on what you are going to do with your rig. For example, I had vehicles that had full lockers front and rear and used arb because they were rock crawlers and locking up the front was only required in specific situations. They were super functional and always worked well both front and rear and the air compressor worked with my tools and pumping the tires up. I think most people never need a front locker or even a rear locker under most 4wd situations but if you do better to get a locker you can turn on and off with a switch. Even my high powered desert can am x3 has front locker I can turn on and off. U don't want to have to deal with steering issues when you engage your front locker when u are just on mild trails.
Look just how capable 4 runners are with just rear lockers..
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