The CX2 does little to prepare you, other than fanning the flames.

The Sim you have will get you there. Keep doing maneuvers on the sim. Hover over one spot. Do low, slow figure 8's. If you have that down pat, by all means, get a 450 class machine. I like the idea of getting a T-Rex 450 and a decent transmitter, rather than one of those RTF packages that often come with a proprietary Tx.