Ah, that makes more sense, I was wondering what the cost trade-off would be between a new server and mailbox licenses on the 3300. If you already have the licenses then it makes it more of an option.
One thing to note is capacity. NuPoint has a far greater capacity than EMEM, so you'll have to look at the number of users and ports etc to find out if EMEM can handle the workload. Also, you mention that you'll have a few 3300's, so keep in mind that EMEM is embedded so it only applies to the phones on that particular 3300 (there is such a thing as Networked Voicemail where you can share mailboxes across 3300's, but that's a separate license option I believe, and you have to have unique mailboxes across your system, a bit more planning).
I think you'll need to look at the layout of your business and see if the EMEM model fits. If you think though that changing to EMEM will reduce your pain then it may not be the right choice. Not that there is anything wrong with EMEM, it's just that you will be trading the issues you had with NuPoint for complaints from the users like "We used to just have to do this before.", because you'll have already upset them by telling them that they'll have to start all over again (lose all messages, record new greeting, etc).