Luxman L505u . . . why not?


I'm getting close to pulling the trigger on one of these--an upgrade from my Rotel receiver. Before I do, I'd like some perspective from the learned A'gon community. First, will it be a significant upgrade from the Rotel? What kind of sonic improvements can I expect? Second, why shouldn't I buy from Audiocubes II? http://www.audiocubes2.com/brand/Luxman/product/Luxman_L-505u_Integrated_Amplifier.html
I know On a Higher Note is the official U.S. distributer, but my budget pushes me towards the less expensive purchase option. Third, regardless of where I purchase it from, it will need a transformer to boost the power to 220. I don't know anything about the possible effects this might have on sound and performance of the component--can anybody speak to this? Is it possible to have the piece modified to accept the U.S. 110 current? I want the piece because it meets my requirements for an integrated: it's at least 100W, it has speaker A/B (I've got speakers in the kitchen and the main living room), it's got a great phono section (I play 50% records, 50% CDs), and it's got a headphone amp. Those are the features I want in an integrated. Any advice, suggestions, dissuasions will be appreciated.

Danny
rosedanny
Well its 11 years later and probably no one will ever read this.My 505 was purchased from Japan in 2009 and i used a step down transformer until recently.Acquired a service manual and now my 11 year old 505u is operating on 120 VAC.The Japanese 100 V units do have a multi-voltage transformer and the conversion takes a few minutes.
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The distinguishing features from the 505 and 507 and 509 are the additional power supply size and output stages.

If you know you are going to play 2 pairs of speakers at the same time the 507 is going to be better.  Also, keep an eye on the minimum impedance, as using A+B requires 8 Ohm speakers in any case.