Metal-Power!

I am probably going to purchase a Klipsch 4.1 system in the next few days, being a high-school student and all I want to get the best buy for my money... 1) Are these speakers as good as the reviews and people claim they are? 2) Are the refurbished sets worth purchasing (I am kinda poor)? 3) Is it worth the extra $50 to get the decoder?