The classic concerto is a fantastic system. The GC and CC amps are identical, so sound quality is the same between the two. If you plan to use nuvonet components like the i pod dock, music port, sirius tuner etc, then the Grand is the way to go. If you're going to use generic source components, I would suggest the classic concerto.

My gut's telling me that you may not be to the bottom of this mystery quite yet, it's possible that the seller installed a classic concerto MCU card into your system.... making it a classic concerto. You could try loading a program for a Grand Concerto into the system. If it loads, you know you have a GC that's not cooked. You can also get ahold of one Key Pad a and see if it works. I would not consider reselling this unit until you know exactly what you're getting.

Also of note, you don't necessarily need a new EZ port, the Classic port will work on a Grand system, the only difference is the number of NuvoNet ports. BTW, the MCU and 6 KP's list at $2300. I would bet a legit dealer in your area would sell for less. Heck I can do it for you for much less but I would want you to send me the unit so I can do the upgrade. The freight and customs would be the killer by the time I sent it back to you.

Can't you go after the guy that sold it to you? sounds like he pulled a fast one on you.