There were no major issues with the installation of the test system in our sample Three Hundred case. From the front of the outside of the case, the only indication of a system being installed is the DVD Writer. Our black drive blended in well with the look of the case. As well, we chose to install the extra included 120mm fan in the upper front fan slot.
Even though the back of the motherboard tray is recessed into the case, there shouldn't be any clearance issues with wide connectors being used. That's an issue that generally went away with more modern cases with recessed trays. The power supply installed without any issues, and we used the included thumbscrews for the mounting.