I’ve used KMC, the SL version, then L then the cheap 10.93. It seems to me that the less you pay the longer they last. Unless you’re really looking save every gram I’d go with a more robust solid link chain like the 10.93.
On another note, I’m failing to see any real advantage to the missing link, other than it’s easier to get your chain off should you need to. KMC say you should fit a new missing link once you’ve undone it 3 times as they wear and become loose. You still need to carry a chain tool around in order to fix a broken chain anyway, plus missing links are over twice the price of shimano pins.
As others have said, I would imagine something is wrong if you are snapping chains.