Hi, I have bought a nice little setup for my bedroom LCD, DVDr, 360 and my most recent purchase Logitech z5500. Comparing the Logitech z5500's to my brother-in-law's Yamaha AV57 I'm not disappointed with my purchase for budget. Sub: For movies and games the z5500 sub is more powerful, deeper and tighter than the AV57's, but does get let down by music as it gets boomy which the AV57 does not. Movie and games: z5500 5/5 AV57 3/5 Music: z5500 2/5 AV57 4/5 Satellites: The satellites on the z5500 out perform the AV57s, sounding more clean, smooth and powerful. I do personally prefer the style of the AV57 though, to the extent I have replaced my front two with Pioneer 100w bookshelf-loudspeakers, which help out on the music side of things. Movie, music and games: z5500 3/5 AV57 3/5 (extra mark for better styling) Centre: Here's the twist and I would also like your input from. This is an unfair test as the AV57's centre has been replaced with a Mission M3c2i centre, which knocks the price of the AV57 up by £130 notes more than 50%. The Mission centre outperforms the z5500 centre in every way. Due to the performence of the Mission centre, I am thinking of upgrading the z5500 centre. Do you think the z5500 would have the impact the M3c2i has on the AV57 by replacing the z5500 centre, with a Monitor Audio Radius R180.