SocMan,
the Xtra Easy comes with a better radio (JR421EX) and the MDS .40 engine that has some detractors. The ones I have seen run well.
The Alpha comes with the basic JR Quattro and the engine is a new design about which I'm unfamiliar.
Of the two I would get the Extra Easy for the better radio. The 421EX allows electronic servo travel adjust, reversing, 3 model memory and other functions not found on the Quattro. Plus it's 5 channels vice four.
Please find an instructor or it won't matter which you buy

Good Luck.