Code Re-Use - Welcome back!
I don't have a problem with libraries that experienced developers have volunteered countless hours collaborating for a cause of new engineering technologies. I try to stay away from reinventing the wheel. Open source libraries and COTS/GOTS software have undergone extensive QA with a cause versus a cost in mind.
Only two cautions: 1) check whether it's being supported and 2) check its currency/date of development. This is the only way you'd know if they have been maintained using the latest technologies (unless you decide to join them). Too big? Use only what you need. Don't know how to do that? Perhaps, you shouldn't be using it, anyways.
