I personally own the CX2 and just purchased the MCX and I'd almost say that the MCX is a little better starting point for the simple reason that it can be used more often. It`s hard to find the space indoors to fly the CX2 unless you have access to a gym or ballroom of some sort, and flying it outside requires perfectly calm conditions. The MCX can be flown any time which will allow you significantly more air time before moving up to something bigger.

The biggest thing to remember is to take incremental steps, or at the very least invest in a good RC Flight Sim like RealFlight and get plenty of practice on that before moving to a 3d Heli. The MCX will give you a feel for the hobby, and many of the flyers I know that regular fly larger 3D Helis like the T-Rex and Blade 400s absolutely love the MCX as it allows them to enjoy their hobby anytime.