No there is no conflict (to the best of my knowledge).
I use W3 Total cache plugin with the php flush() function for my blog. It actually helps in immediately rendering the ready parts of the page rather than waiting for the whole page to load (this gives the impression of a faster download). The flush code should go immediately after the </head>:
<?php flush(); ?>
Why don’t you try it and see if you get any issues.
Hope this helps,
Boutros.
This is from W3 Total cache FAQ:
I see garbage characters instead of the normal web site, what’s going on here?
If a theme or its files use the call php_flush() or function flush() that will interfere with the plugin normal operation; making the plugin send cached files before essential operations have finished. The flush() call is no longer necessary and should be removed.
*So eventhough things were working fine on my blog, it might not work for others. I am not sure about other caching plugins.
Boutros.
