I want to apologize for my very late reply on this topic. However, I do have some good results to post. I have been using this router with the QoS mod firmware solid for a few months now on my work internet connection at home. The connection is a 50/10 DSL Fiber connection that I regularly hammer with uploads of larger files. This is the most stable the router has been for me. I do still have the heatsink installed in it and it still gets quite hot. With it being stable though, my guess is the cap D-Link has implemented in the stock firmware is at least partially to fault for the instability. One minor note about my experience with this router whether running on the modded or stock firmware. It clearly doesn't have the processing power to keep up with multitasking over a network.
Thanks, Furry, for passing that on to me and thank you to the creator of the modded firmware!
By the way, I really am liking the new forum colors and style.
I just wish the buttons were slightly larger.