I have use Joomsef for a long while so i want to share my comment about it. This is not true that Joomsef cant handle large site. I have large site with +250 articles and 80k+ (yes 80000+) of products in catalogue (Virtuemart) and JoomSEF handle it with no problem in a normal non dedicated server. My friends other sites runs with commercial JoomSEF too without any problems with kunena, joomfish, jcomments. Support might be better but joomla community can help too if any problem exist. Is a great value product and really do his job!