If you go with the mcx - get the new mcx2. I don't have one, but I understand they improved it quite a bit over the first one.
I have an MSR and I love it. I have flown it countless hours in my living room and I never come close to getting bored.
If you're starting out - make sure that you start out on low rates on your RTF transmitter (press down the right stick till you hear a beep and the red light on the radio is flashing). This will make it much easier for you to control, especially w/ the MSR which is really fast!!