A little background info first. The company I work for is being put under pressure by their IT consultancy contractors to replace their current dedicated Exchange server. The machine is working perfectly and performing all duties that are required of it. It's not slow or unresponsive, although it's 5 years old. It's running Windows Server 2003 and Exchange System v6. It has 4GB of RAM, a Xeon 3065 (2.33GHz), and 2HDD (1x250GB and 1x150GB), both of which are about two thirds full. It is actually using somewhere between 2-15% of it's CPU and 1.3GB of it's RAM. The exchange server only services about 30 mailboxes and a webmail feature, as far as I am aware.
The reason the IT consultancy is giving for pushing the server being replaced is that support has run out for windows 2003 and they fear hardware failures may be more likely because of the server age. I understand that 2003 is past Microsoft standard support, and that extended support runs out in 2015.
So, my question is... what would be some common reasons to replace the server and should we be replacing it?
Sub questions: Is 2003 support really important? Is hardware failure a concern (even though it's running perfectly)? Would you bother replacing it yet? Are there any cheaper alternatives to solve this issue?