i have used a couple other frameworks, codeigniter, cake, drupal, joomla, some CMS, others not, and Silverstripe now a bit, it seems a little slower in performance than these other frameworks. But it does have some cool pieces and features that really make implementation fast. So if your site istn't that big and you're not concerned about really high performance, this might be a good choice. But i might look into the others if performance (speed, high volume, etc) is a requirement.
