In my opinion, the XA gives me the choice of apertures and it is the only rangefinder in the XA series. The XA2, if i am not wrong is leaning towards the functions of an LC-A.
I own XA,XA1,XA2 and XA3, on my daily walkabout or to work XA2 is always with me,cos no focusing needed ,only zone selection.
For XA you can be more creative in your shoot,
XA1 is the simplest of XAs;p