Well funny you should ask about this as I have personal experience both ways . . .

I just recently installed the Kenwood KMR-D562BT radio unit into BOTH of my SRT6 roadsters. That is a FANTASTIC head unit and I would highly recommend it. Just changing the head unit made a world of difference in the sound quality (and you won't need to do that resistor thing in the door speakers).

I bought radio units from this E-Bay seller . . . (Note this link takes you to a different model radio . . . a KMR D365BT) but this is the seller I bought from) . . .

Kenwood KMR D365BT Marine CD MP3 WMA Player Bluetooth SiriusXM Radio Ready New | eBay

Now on to your other questions . . . In my black SRT6 roadster I also replaced the OEM infinity amp and ALL of the speakers. I had this amp installed which fits in the OEM amp location . . .



It sounds really really great and I'm more than satisfied with the results. The ONLY negative issue is that I'm picking up some ignition "noise" through the sound system. That may actually be an "installation" issue and not an issue with the hardware. Need to look into that further.

On my SSB roadster I left the OEM Infinity AMP installed AND the OEM door speakers but had to replace the subwoofers because they were shot (the foam around the speakers had deteriorated).

My conclusion is that the factory OEM Infinity head unit is really a POS and should be replaced. The OEM Infinity AMP, however, is more than satisfactory if you put in a new head unit and the difference is night and day even with the factory OEM amp and factory speakers. If your OEM speakers are still in good shape I wouldn't bother replacing them. Just putting in that Kenwood head unit will provide GREAT results and you should end up happy. Start with that Kenwood head unit and move on to speakers and amp only if you need to . . .

Best regards,
Bob Davis (Red Dog)