The annoying thing is you can't directly pitch frameworks against each other - because they were all built for a slightly different purpose.
Personally I'd probably pick Symfony. But Laravel and CakePHP are good candidates as well.
Laravel wins for community.
CakePHP wins for ease of understanding
Symfony wins for being more robust.
So, CakePHP is good for small projects - so for me it's not great. Whilst Laravel is good, great even, I have been reading up on it and it seems it's meant to be for more experimental use. So symfony for me, even though it has the highest learning curve and is the most complex.
Personally however, I've never been particularly happy with either PHP or it's frameworks. There are many articles online that discuss what a terrible language PHP is but PHP isn't celebrated for that reason - it's celebrated for it's environment. And the tools/frameworks tend to make up for it's downfalls.
Further to this, I would suggest looking at HACK and it's HipHop Virtual Machine (HHVM). The HACK language aids in removing some of the more important issues with PHP as a language and the HHVM helps run everything really quickly. (Should have Windows support before xmas :D).
Hope this helped.