If it's an option, then limiting high quality ICs to 1 to 1.5 meters is going to be best AND keeping the speaker cables down to 10' or less. However, that's not always possible. You have to weigh WAF, your own tastes, etc. into the equation. With luck, any compromise will be have a very small impact on sound quality. Your awareness of the issues wiil likely lead you to spend the money wisely.
Dave
Dave