If I'm reading that code correctly, it will convert all tags in the content section, which may not be what you want (e.g., chunk tags for notes of various kinds).
Fixedpre will let you put fixedpre tags around just the tags you want to show rather than execute. It will also let you style the fixedpre sections with CSS. AFAIK, fixedpre will never require you to manually insert entities, which it looks like the other plugin sometimes requires.
Another plus is that fixedpre will work inside of pre tags, so you can have different styling for inline tags and blocks of code.
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