I might have the chance here soon to traid my Alpine CDA-7875 for a newer CDA-9881 h/u. Should I do it? I want to be able to play MP3 CDs and CD-RW CDs but I'm not shure if I want to go from 4volt sub preout to a 2volt sub pre out. my 7875 is also 65watts x4 right off the h/u IDK what the 9881 is though. Both h/u are in great shape and work flawlessly. My new RUE-4187 remote works on the 9881 as well. So, should I do it?