Hey Geoff --
What mics are you planning to use? Not all mics sound their best with all preamps, so if you do go with an MP2 pre, make sure you've listened to the mic/pre combation in some tapes first.
Everything mentioned so far is spot-on. Here's my $.02, I'd go:
great mics > Phantom power > line transformers > D100
Not only is this stealthier than the MP2, but it's also a lot less expensive, or at least allows you to put the MP2 money into a set of higher quality mics if you so choose. Line transformers can be had for ~$40/pair and are a great, inexpensive way to apply clean gain so you can go line-in on the D100. You can always sell the phantom power and line transformers later to get a pre, but this way when you do, you won't also be wanting to change the mics for an upgrade.