After a careful consideration of the posted answers, I think the regex is the right choice for THIS particular case because:
The XML in question is retrieved via LWP, so by the time it needs processing, it's in a string, already in memory, so the possible efficiency of the library reading a file is negated.
The site/API I'm retrieving the XML from is versioned, and I request a response from a particular version as part of my call to it, so the format *shouldn't* ever change.
So, all the perfectly valid reasons to use the library in general don't apply enough in THIS case to justify the added complexity. Thanks for all the discussion, it helped.

In reply to Re: XML parsing vs regex by derekstucki
in thread XML parsing vs regex by derekstucki

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