The X-A1 is essentially a cheaper version of Fujifilm's popular X-M1 and the least expensive model in the mirrorless X line. The most notable difference between the X-M1 and the X-A1 is the sensor. The X-A1 still has the large, APS-C sensor, but it isn't Fujifilm's X-trans design, which eliminates the low-pass filter and results in very detailed images. The X-A1 is also constructed with a less expensive exterior and has a single color instead of the retro two-tone look. If you can swing the extra $200, go for the X-M1, but the X-A1 is still an excellent option, offering a DSLR-size sensor and Fujifilm quality for about $600.