When I was a young network technician, (back in the days when I was like 16-17), I just loved D-Link’s business products. Everybody knows that the (cheap) consumer products from D-Link works like crap. But I was a huge fan of the D-Link DFL series back in 2003. My own firewall that I had at home at that point of time was a DFL-700, that was a regular D-Link box, BUT was shipped with firmware from Clavister. (Clavister software underneath with D-Link web GUI on top). Even today, I can actually miss it sometimes in a nostalgicall way. 
My theory regarding the crappy D-Link consumer products during the last years has been this:
“The device (hardware) is not the problem. It’s “only” the stock firmware that has some serious issues…”
Until this day, I have never had a chance to prove my theory as a fact. But now, I have finally ordered a D-Link DIR-600 just for the purpose of evaluating the hardware (not the stock firmware!). DIR-600 is actually supported by DD-WRT and what I will do with it, is to flash it with DD-WRT and actually use it as my primary firewall at home, protecting all of my networks (including DMZ)! I will have all my devices traffic flow through this firewall and do some serious tests with it regarding many facts, such as throughput, functionality and reliability (nothing that the original firmware can provide).
I will let this test go for at least two weeks and I will post the result here to share with you guys. What do you think is the problem? The hardware or the software? 
// Fredrik “DXter” Jonsson