While the Monster Cable may sound good to your ears, I think you may be very surprised to learn how much difference cable upgrades can make. The best advice I can give you is call The Cable Company, ask for Steve, and consider his recommendations. You can audition cables at home, for a small fee, and see first hand what works in your system. You will get a thousand different suggestions from us A'goners, but hearing is believing. If you decide to purcase, the audition fee is applied to your purchase.
I think that is the best way to go about cable upgrades. You can drive youself nuts about it, so many options.
Also, many A'goners recommend Signal Cable Company, supposed to be excellent cables at a budget price.
Best of luck,
Dan