Large file uploads and drag/drop

Hello AlertSite gurus,

I'm struggling to figure out how to test performance of a large file upload into my web application - by large I mean 50MB but would occasionally like to go 1GB+.

I'd also like to be able to test a large (250 file) drag and drop of <500Kb files.

Does anyone have experience of getting this to work ?  there seem to be limits on filesize for dejaclick but I haven't been able to find much documentation about that.  
Many thanks for any help, suggestions or pointers.
Have a great day.
Bert.