I have a 2005 X5 with a bad DSP Amp. I see alot of DSP amps on ebay that say they will work in my vehicle. But their part number is not the same as mine. But they look identical to mine. My part number sells for close to $600 the others are $200-300. Do i have to get my exact part number??

I know I have to get one for a vehicle with Navigation..
Thanks