I am interested in finding the most reliable method for uploading files in PHP. I need a progress bar with the upload.

I have tried SWFUpload but it randomly issues an I/O Error. Even if the same file is uploaded sometimes there is an error and sometimes there is not. I have configured all the necessary INI/Mysql/Apache directives to accept large file uploads.

So, I am looking for alternatives as a Flash based solution has not worked. Would Java be more reliable? I have also looked into PHP with APC.

I definitely cannot afford these random errors, so any help on reliable software / suggestions on how to minimize them would be appreciated. 

Thank you.