I'm running a Luk now. Last one I took off was Sachs, neither one gave/have given me a lick of problems over ~25 years, just replaced the Sachs when I changed engines. I could have kept running it, and I smoked it a couple times. In looking at Rockauto Luk is the only one of the two that still offers a step up from "daily driver grade" (there are higher grades of both), and I would probably go that route if I was repurchasing. Cheap materials/design are not something you should have to deal with when running a transmission that should handle anything you throw at it.
Stay away from the three finger designs (if you can even find them still) if you want good clutch feel.