I can't speak for most people, but I have RPC1 on half my drives just because I can. Only ran into one problem on my 4570, but that probably had nothing to do with the RPC1 portion of the flash. As I said, there is no reason not to have it. If for some reason you run into a very rare disc that insists on a region, you can always flash back to the non-RPC1 version and go from there. I have yet to see a region one disc where I noted a problem. BTW, flashing back and forth is not a problem as long as you follow the cautions; no power off, no applications running, no disc in drive, and always make sure you have identified the correct drive for the correct firmware.