I’ve been through a few brands, and for me, Shimano seems to last he longest. Shimano’s chains have never broken on me either, while others have. I will say, though, what has extended chain life for me most significantly was when I went to chain wax versus an oil. I used to clean my chain every time I oiled it. Now, it gets cleaned far less, and I just add more wax from time to time. Before wax, I’d run though at least a couple of chains a season, starting each season with a new chain, and probably over extended the use of chains. Now… one chain a season. For reference: I do have a Shimano XT drive train. I tend to stay in higher gears when climbing, so I do put a good amount of pressure on the drive chain. I don’t ride wet/muddy conditions, but sand/fine dirt is common. As for cost, I guess I never really paid attention to the difference between chains.