For me the main turndown of using PHP is when I need to host the PHP website, php-fpm and Apache+mod_php seem to be the only two options. (FastCGI doesn't even have a proper specification).
I would be a little bit careful while using swoole. They added some code that loaded code from a third party server [1] (a core developer who seems to be located in china). Even though it seems like they removed it doesn't bring a good feeling. It seems like there were also some disagreements with a contributor who maintained the website of swoole and he forked it [2]: https://github.com/openswoole/swoole-src