I own a Gerber that was my faithful hunting partner. It is a little beat up, the flathead screw driver was twisted when I torqued a screw a little too much, the file blade was covered in orange paint dust and the saw blade snapped in half while cutting a small branch this hunting season. After the blade broke, I contacted Gerber, they told me it has a lifetime warranty and I sent it back to them. They replaced the screw driver, the file and the saw blade for no cost and even included a new sheath. Gerber stands by their products and returned my Gerber to me within two weeks. I will be a Gerber customer for life due to their products and outstanding customer service.
With that said, when my Gerber was out of commision, a buddy bought a Leatherman Surge for me to finish the hunting season with. In my opinion, the Leatherman is a much stronger tool. The blades are thicker, the tool is thicker and the steel used seems higher quailty. I'm very pleased with my Leatherman so far and it has replaced my Gerber as my hunting multi tool. The Leatherman has a 25 yr warranty.
My Gerber hasn't been retired however as it is now the multi tool that I carry in the truck for emergencies. I like the Gerber too much to retire it so I figured it would still get good use in my truck.
I'm not sure that you can wrong with either brand. The Gerber is lighter in weight, cheaper price point and has outstanding customer service that stands by their lifetime warranty. The Leatherman is expensive, it is HEAVY and has a 25 yr warranty.