Been struggling for a while with my 5k LG and my 3840x1200 Lenovo, as the supplied cables caused a flicker in some applications when running at any refresh rate above 60Hz. And your 120Hz & 144Hz displays aren't appealing at 60Hz.
So I figured I'd try a new DP1.4 cable that was on the certified list at displayport.org to see if it was just crappy cables. Sure enough, these startech cables are 100% flicker free. Also isn't sensitive to being handled like the LG bundled cable was. Simply touching the cable or moving it would cause it to lose sync. Luckily they're both connected to Nvidia GPUs, so they use the virtual display adapter which can recover from brief losses of sync without crashing whatever it's running.
Don't know about the durability yet, but I don't disconnect them too often, so hopefully they'll last a long time. I figure the lifetime warranty should cover it if there's a problem, as startech has been good to work with the few times I had problems with some other, older products. So I expect it should be fine if I have a problem in the future.