No Mopar10 for me, but have an RT with the lowly 130. I do plan on upgrading as time and money allows. At first, I had thought about doing an aftermarket head unit, but the more I think about it I would prefer to grab a Mopar unit, even if used from eBay or a junkyard that still works.
If Nav isn't a requirement for you, then check into the REN units. I read something on these forums that indicate they have the U-connect BUILT INTO THEM. That will save you about $200 by itself. FYI, a REN unit I was recently tracking on eBay sold for $300. Of course, if your car doesn't have the auto-dimming rear view mirror with dual mics, then you will have to get a microphone to get U-connect fully operational. A lot of guys like the mirror because it's the most stealth looking and closest to factory, but the mirror is around $300+!!!! Alternatively, I've heard of one guy installing the microphone included with the U-connect kit somewhere down where the dash and center console meet so it's almost invisible. That is probably the option I will pursue unless a mirror drops into my lap for next to nothing.
All that being said, you will still need the IPOD cable to enable control with the radio head unit and/or steering wheel controls (if you have them). I think those are around $50-$100 and there is a MOPAR parts # but I don't know what it is. I did read something where some work with iPhone 4's and some don't. I think white vs. black. Don't recall the details, it was a late night.
If you want to add the steering wheel controls, that is possible too. Got to get a few parts and have the dealer do some programming. Here is a link to that thread (it's a long thread):
http://www.challengertalk.com/forums/f5/adding-evic-controls-20575/
That link also contains info on adding Homelink & EVIC, something else you may want to add.
Lastly is the speakers/amps. I wouldn't have a problem using aftermarket components here. Just use the factory locations.