It ain't free, I can tell you that. We've just upgraded with SQL and Exchange server and Remote agents.
Only good thing is that for the three remote servers we only had to pay for one remote agent as the SQL and Exchnage act as remote agents unlike previously, when we had to buy remote agents for all the servers.
GUI is nicer and there are some nice guide me wizards that'll help you work out exactly which backup you need or want to do! Apart from that can't really see much difference.