I know I'd want the best rope available for the money if my hide was relying on it! The kind of mountain climbing that requires rope and harness is an expensive hobby any way you look at it. Most people who are real enthusiasts aren't going to mind paying extra for reliable rope. As I said: their lives depend on it. Cheap rope might mean a wheelchair for life, or worse, being sent home in a body bag. Chintzing out on mountain climbing rope just isn't worth the risk.