I'm getting a new HU to replace my Sony Xplod MP3 player from last year or so. I need from my new player with high powered outputs to run front speakers by themselves and utilize separate signals to tweeter and midbass for superior imaging and sonic tuning abilities. The unit will be hooked to amps for the front speakers and of course the sub, so built in power is not a necessity. I also need a lot of control over the sound, a large EQ preferably over 8 band and speaker time correction are preferable. The new head unit must play MP3s, with good speed, have XM or Sirius compatibility, and control a CD changer if I were to get one. The brands Ive looked at are Alpine, Blaupunkt, Clarion, Pioneer, Pioneer Premier, and Sony. I'm not restricted to these, iv just checked them out I don't necessarily need a full color motion display or LCD screen, but will take whatever the HU falls within description of what I need. I'm open to suggestions and comments on any brand, share your good and/or bad HU experiences, its all helpful in making this huge decision. The Alpines and Clarions, Ive looked at are around $550 in crutchfield, and the Pioneer Premier, Blaupunkt and Sony HU's have been between $350-$650. Also can anybody explain the main differences between Pioneer and Pioneer Premier Head Unit's? Is the extra cost justified, and in what circumstances? Also interested in Blaupunkt feedback, nobody seems to run em' or talk about them, I think they're pretty neat, any experiences there? Any price within 200-800 region will work out. I want the most functionality, and audio quality for the money, the best available in that range of price. Appearance, and styling aren't really very important, as long as its not ugly... I promise, this is the last thing: what are your opinions on HD radio? could it be worth the huge premium in cost for compatible receivers? Any experiences, or opinions?. Thanks for helping me out, just tell me if you need more info, or if my info. is to broad.