Here's another thread that goes into a lot of detail about this:
importance of exact match, and ... "where'd all the searches go?" « Noble Samurai
(Note: This thread is only a few hours old)
I choose phrase-match because it's more broad than exact match (which often means you pick up a little extra traffic around the edges). Plus, because of the nature of phrase-match, I find it's easier to work out word order using Phrase Match.
There's certainly no harm in checking keywords using Exact Match though - it serves its purpose too.
Brent