Quad & hexacopters are all the rage in RC flight right now. Well, they are with a particular subset.
Most are gyro-ed out the backside and some have limited UAV/programmable route capability.
Even with all the gyros and computed aided flight, getting that fancy with the maneuvers is not as easy as it looks. Start out with that sucker and expect many tears.
Also, any of the RC copters will be pretty inefficient with power, just the nature of the beast. For a similar investment in lipo batteries and motors, you can design a fixed wing RC aircraft that will lift a LOT more.
I am fairly new to RC, but I can keep a reasonable 4-ch (throt, elev, rudd, ail) fixed wing in the air, but only a coax rotor copter.