The cable running to the antenna is RG-58, I know that I've heard RG-8 is better, any truth to that?
Yes, there is truth to that. RG-8 is a great coaxial cable and in most cases offers less signal loss than RG-58 does. Belden 9913 tops RG-8, but the stuff does get expensive.
Hope this helps,
P.S. If you do a quick search on either of the coax cables here in this forum, you'll find a wealth of information and/or links to outside references.