Both OM and I,A were produced by Cameron Mizell (Chango) which may attribute to some of the similarity. To be honest, I thought the difference in the cleans in I,A and FAIM were due to producer change as well as the singer geting older (I think they're all pretty young). I think all the cleans have always been done by one of the guitarists/bassist but I don't know for sure.
ah ohkay. yeah i remember finding the demos online when they were still relatively new. pretty high views for myspace. (im a huge dork when it comes to finding bands before they were famous or signed in this case, plus im pretty close to their hometown) really excited for new stuff.