heartland cables???

So I bought some Heartland cables a few years ago. I think I remember the site saying canare cable was used. I have some speaker cables and some ic's with the eichman bullet plugs. So how good are these things? How much money would it take to upgrade? Right my setup consists of Klipsch kg3.5's, Aragon 2004 mkII, Yamaha rxv-659, and a cheaper Pioneer cd player. How close are the cables to a weak link?