Z5500 BLOWS THE Z906 OUT OF THE WATER.
These new speakers suck compared to the old ones. Crappier build quality, less sound quality.
The extra inputs are the only good thing. I don't think the Z906 even comes with mounting stuff for the speakers like the Z5500 did (not sure about that though).
You can tell how [censored]the Z906's are when people are still trying to buy the Z5500s at $500+.
Omg the surround sounds are surrounding us! Looks awesome, too bad I cannot hear them.
I picked up the Z-5500's back in 2008 while I was in Iraq. Since there was really no noise rules there, and we worked in a rather large warehouse, I cranked these bad boys up as loud as they would go. Surprisingly the volume, bass, and quality was absolutely amazing. I was surprised that Logitech could put out such quality.
Today my wife has since confiscated them, and requires they be hooked up to our tv in the living room at all times. They are still going strong even after going through numerous sand storms, international shipping twice, and being completely ripped out by a curious toddler.
Now seeing that I was able to pick up the z-5500 on amazon for only $250, I'll wait around to see if these drop in price as well. Maybe one day daddy can finally have his surround sound on the gaming computer. [:P]
Edit: After posting this I checked around real quick to see what they are going for. There's one refurbished unit up on Ebay right now for $269.95 + free shipping.
http://www.ebay.com/itm/130708236127?hlp=false , While I can't afford it right now, maybe somebody else here can? It's well worth it.