I know a little bit about home recording and have gotten some decent sounds, but I don't know very much about mic pres. Right now I'm using an mbox. I am looking into getting a royer r-121 but don't know if the mbox preamps are good enough. If they aren't, could you recommend something for under $500 that would give good results. Also, how would you rate the focusrite preamps that come with the mbox? thank you.