Logitech Z-5400/Logitech Z-5500

hi, how do the 5500s compare to the 5400s?
are the 5500s worth the extra £100, or should i just get the 5400s and save the money?

i will be using the onboard sound on a sn25p (may buy a seperate sound card later on).

i preffer the looks of the 5500s however im not willing to pay the extra £100 if the quality isnt much better.

thanks

nebs

EDIT: i will be using the speakers for games/music/dvds
also would it be possible to use them with my TV? - if so what do i need for this?

anyone?