Check whats your need, if you are building up much bigger apps go for a fully fledged framework, rest for small apps you can use microrouters , according to your need, each has its own unique features.

For small apps, you don't need a "router", period. Routing is done by the file system and placing .php files in directories!

One of the benefits of using a url router is access control - you could have a problem with just letting every file be executable by url, especially if you happen to have a remote file inclusion issue anywhere. With a router you know explicitly what can get invoked and what can't.

Although, doing it without a router is probably always going to be faster.

A late trick I discovered, was that you can configure your php instance to inclued a file with every script. For example the following can be added to .htaccess:

  php_value auto_prepend_file 'before.php'

You can then use that for bootstrapping, front controller and to limit access. Can be a bit clumsy, but it's nicely divorced from simple page controllers.

neat! this beats putting an include at the top of each file...

It certainly does.

I personally would still prefer a router but I know of a project which was written almost entirely in sprawling, procedural PHP that might benefit from this. Although I do wonder what the performance hit would be.