in reply to best xml parser to use
I'm not sure how it stacks up against these criteria, but if you're not 100% sure that your incoming data is entirely valid, you might want to check out XML::Liberal (a standin for LibXML). Avoiding re-parsing a large XML file because of a small nit might be worthwhile form of efficiency.
The author gave a nice Lightning Talk about it at YAPC::NA.
-xdg
Code written by xdg and posted on PerlMonks is public domain. It is provided as is with no warranties, express or implied, of any kind. Posted code may not have been tested. Use of posted code is at your own risk.
In Section
Seekers of Perl Wisdom