I would not get a Micro Rs4 if you're gonna leave it completely RTR stock. It's no fun. Go with a Digi Q.
Also, with the Micro RS4....If you catch the modifying fever with this RC like I did..get ready to see your money go bye-bye! I have spent around $700+ on my Micro RS4, testing out different setups and motors. I finally found the right combo that I am comfortable with against 10th scale RCs.
With the Digi Q, I think the most you'll probably spend is around $200 tops, depending on what exactly you buy(controller,bodies,accessories,etc,.). For instance, I am planning on buying a Digi Q-R($40-60) very soon and then the Special controller($20-50?). Maybe a couple bodies also. That's it. From reading alot of the Digi Q threads, I should be real happy! I don't know too much about the Digi Qs, but that's why I'm here in this forum.