4u case designs have gone out of favor for co-locations, but they offer more drive density for storage servers when rack space is plentiful. The 4u height also gives users the ability to run 90mm and in some cases, 120mm fans for CPU cooling. I know some will cringe to hear about overclocking in IT, but high frequency trading is really taking off and that market is taking advantage of all the CPU power they can get. The RSV-L4411 case delivers excellent cooling for the system components as well as the HDDs. The cooling is quiet and that makes this case a good option for audio and video studios that don't have a dedicated server room.
I think for the DIY crowd, price plays a large role in the purchasing decision. At $199.99 plus $11.99 shipping at Newegg, the RSV-L4411 is strong in the value department. You can spend less money on a rackmount case that feels like it's made out of tin and flexes in all directions under its own weight or you can purchase this case with zero flex, even with the case cover removed, and get 12 acceptable quality drive sleds.
Any shortcomings we found, the price more than makes up for. If Rosewill could add a way to secure the USB and button cables to the inside of the case, it would be nice. One of our drive sleds needed a bit of adjustment on the plastic rails and the handles stick out a bit far for some improperly configured racks. Other than those issues, we were very pleased.
After looking at the other products offered at Newegg for rackmount cases in this price category, I couldn't find another case with this many features.