compare the memory specs
DVC typically use expensive low-latency stuff. In video editing the latency can be more important than the actual speed
Also I'd guess that their quote includes a video editing software suite??
one thing about buying from DVC that isn't on their price list is the support they give: they'll happily give free help and advice over the phone years after any warranty expires. They reallya re good. The value of that depends on what software you use and ho well you know it!