Recommendations for PDF Creation Libraries?

I felt the need to resurrect this old thread because I finally discovered wkhtmltopdf. I had been using dompdf for years, and dompdf is just almost impossible to make a layout that is complex. wkhtmltopdf makes dompdf seem like garbage. I created a few documents with it this morning, and didn't run into any rendering bugs or errors.

how do you integrate wkhtmltopdf in codeigniter?
thank you.