Can't Make Up My Mind on First Build

For my first drifter, I would like a RWD.  After numerous hours of researching, I find it promising to choose between the Sakura R4 or MST FXX-D.  

What are the advantages and disadvantages to both choices? 
How easy will it be to get spare parts?


I sold all my tools and equipment for my previous r/cs below, so I'll be starting from scratch. 


My Previous R/C Experience:

-Early 2000s, My uncle and I built my first nitro r/c.  HPI RS4 II.
-Couple years ago, I had a 2WD Traxxas Slash.


Thank you!