This feature is amazing.

VERY reasonably priced, extremely full-featured, easy to set up, fantastic performance, just an all around winner.

There are a pile of great features but I will not replicate them here

There are some nice advanced features such as SNMP support and the ability to gain shell access and install your own software (there's a decent plugin community).So far, it's been flawless in performance (aside from the caveat below), excellent

My personal favorite feature of this card is its LINUX support