Hi Sunny,
I peform professionally with a Yamaha Tyros2 & own both the MS02's
MS02 System with Bose 161's:
and the Logitech Z5500, and without a doubt, the Z5500 system wins hands down (no contest) in both power output and sound clarity & quality, especially after 6" mid speakers were added to my customized Z5500 cab built 4 me by my good upstate buddy Pose
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:
Logitech Z5500 System (Custom configured):
The only real advantge with the MS02's is much lighter size & weight of the sub woofer, but most of all, the convenient ability to instantly mount (swivel base + quick release) the satellites directly atop the KB. Unfortunately the stock MS02 satellites sound crap, but after replacing them with a pair of Bose 161's the system delivers decent sound quality for those small initimate parties & NH venues up to 50 people. The Z5500's on the other hand can accomodate up to 275-300 people.
I agree with BOTH DonM and Gar Diamond, because until I finally actually purchased & heard the Logitech Z5500's for myself thru my keyboard, I too wasn't convinced.
Scott
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[This message has been edited by Scottyee (edited 10-31-2008).]