I've ordered several cases/chassis from The diyAudio Store, and have always been happy with the quality of the product.
In previous builds, I used the Galaxy-series of chassis. This is my first with the Mini Dissipante. I added the optional bottom plate, and I'm glad I did: it adds significant rigidity and "confidence" to the overall design. Also keeps the bottom of the case looking nice, as components get mounted to the internal bottom plate (rather than the true bottom of the chassis). If you're building with the Mini Dissipante cases, I definitely recommend adding the optional bottom plate.
Shipping on these is unbelievably fast. I also had custom machining done, the website said this would add extra time (5 days IIRC) to my order. The case was actually delivered to my house (Italy to USA) in less time than what was supposed to be added to total fulfillment time! I wouldn't have complained if I had to wait, but the turnaround time is nothing short of impressive.