Own a Sunfire Signature Cinema Grand????

I am really curious about the sound quality of the Sunfire Signature Cinema Grand power amplifier. 405 watts through 5 channels is alot of power but I am more concerned with the bi-wiring of the 3 front channels in current/voltage mode. Would this be a huge benefit in sound quality for a home theater set-up compared to a non bi-wired amplifier/speaker hook up. Give me your thoughts.....

I have the unit in my showroom and upon a customers request ran it both ways , there is a big difference when you are on the 7.1 input comming off a good source, not so much using digital feed.
I have this exact amp in our HT and it is a fine piece of gear. Our HT is Martin Logan all around so I wire the front 3 with current on the panels and voltage on the woofers, sounds nice and detailed and no brightness/leaness at all. For the price they are hard to beat. I hope this helps you out some, good luck.

When I had this amp powering my front speakers, there was a considerable difference between the 2 sources and I was able to bi-wire successfully. It sounded better that way than either current or voltage alone.
You'd do better buying separate Signatures for each channel: Much better channel separation that way. They could be used Signature 600s, or whatever Signature amp is least expensive used.

IME the Sunfires have issues with RF. These can be solved, though, with a Marigo Ultra 5 power cord.
The preamps might conceivably have RF issues but I own two (one 2-channel 600 and a 5 channel 405) and RF isn't a problem at all.

The best amps I've ever owned. Or likely to own.
If you tried the power cords, you'd hear the difference instantly.

I don't know whether they offer the money-back guarantee on power cords (they do on their mystery feet), but if they do, you might consider trying it out.