www / system.net.webclient alternative?

Is there an alternative to these for downloading files in unity?

www is painfully slow. system.net.webclient is great on desktop but doesnt work on ios and android. the performance of www just isnt aceptable for the files i need 100MB +

i tried the solution in this question but this is as slow as www and didnt work on a quick android test i did http://answers.unity3d.com/questions/322526/downloading-big-files-on-ios-www-will-give-out-of.html