Finally, we have replaced our mail gateways to Iron Port C350. We deployed 3 Iron Port in our network and God knows how much we suffered with old mail gateway appliance. It was horrible experience including support and the product itself. No need to mention names. Those of you know me personally I will recommend not to buy and what to buy as dedicated mail relay gateway, ping me at any time.
I will write more about Iron Port, let me tell you, incredible device, awesome support engineers so far. The Shell is UNIX, and most of the basic Unix commands works like a charm. Incredible flexible and noticeable powerful mail gateway, no wonder 90% percent of the government business using Iron Port in Washington DC.
Be carefully when you decide to buy dedicated mail gateway, wrong decision will give you big head and lost of revenue eventually.