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
"The only big difference between the 505u and the 507u is that the build quality of the 507u is higher.
Paulyh"

So 507u cost twice as much as the l-505u but you do not hear much of a difference in the sound?

To me it seems there should be a obvious difference in the sound quality for that much difference in price.

What improvement in sound have you heard with the L-507u over the L-505u?

Hi Jbsl43, I did not really mean that the sound of the 507u and the 505u are exactly the same, but they really sound a like. Unfortunately I have not had the 505u and the 507 at the same time. Their was a month in between with an accuphase e408. And I only had the 505u for 2 weeks. So I was not really able to tell the big differences.

The only thing I directly noticed was that that same warm satisfying feeling came over me when I plugged in the 507u after the e408. The same deep bass, the ease and tranquility in the sound I heard with the 505u.
is it worth buying or saving up for the 507u over the 505u ?
The difference i think is almost double between these two units.