Would the Marantz SR 5001($800.00)CDN or SR 6001($1150.00 CDN be an upgrade from my Onkyo SR701 receiver which sell for about ($935.00) CDN? The rear speakers, centre channel and subs are powered through my a/v receiver and the front speakers are powered seperately through an Acoustat Trans Twin Nova 200 power amp. I use the receiver about 50/50 for music/video. Also the NAD T753 ($1290.00)CDN was recommended to me? Any thoughts would be appreciated. Thanks.