PHP Frameworks Yii vs Symfony2
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i'm starting a new project using PHP, this is my first time working with the language. However, i'm a very experienced web developer.
The new project i'm starting is the flagship project of our company, which we plan to continuously build, upgrade & improve upon it over the years.

From what i read online the showdown came down for me to Symfony2 & yii.
Although i know one is considered "Full Stack" and the other one isn't, i would still like to get an idea which you think is better, given the aforementioned parameters?