I originally purchased this for use as an overhead location-audio source for film work, however it's such a good mic it's seeping into my other work!
Build-wise, it's the same as any other Superlux microphone - built like a tank, and then some. It feels a lot more expensive than it actually is, and that's not a bad thing, as it can take the battering that the outside elements give it. The sound quality is very clear and without distortion, even at the higher SPLs.
It comes with a clip, a wind cover, and a 5 pin XLR to 2 x 3 pin XLR cable. I'd reccommend doing what I did and getting a seperate shock mount (due to the slim body it fits the t.bone SSM 4 very well), and invest in a better wind sheild - I used my BOYA Furry windscreen from my Tascam DR-40 with it no problems. I cannot vouch for the cable quality as I used my own custom cables due to required length.
Overall, the E523/D is what I've come to expect from Superlux microphones - good quality sound at an affordable price, and built like a tank. Worth every penny.