I don't think your more general question (that is, the node-title :) has a final answer, and the more specific question ("Which would you choose?") neither.

In my case, the answer depends: private or job project?

• private: roll my own, if interesting enough
• job: use a Module if it's feasible, otherwise answer2, including copying from Modules.

In my experience, reusing code from other, more experienced coders sooner or later leads you to better understand the problem-domain(s) you're acting on, as well as the language of the day, while saving a great amount of time between project start and delivery/deployment

after all, I'm a coder because I'm lazy :-)
regards,
Tomte