It's been a few years, but I used dompdf because of its simple HTML to PDF converter. I generate my document in HTML, then convert. It was more of a proof-of-concept thing and it never went any farther than that. Did pretty well, I thought, at the time.
$dompdf = new DOMPDF();
$dompdf->load_html($html);
$dompdf->set_paper("Letter", "Portrait");
$dompdf->render();
file_put_contents("mypdffile.pdf", $dompdf->output());