Well I've got an IPad for some days now and was fiddling with a bunch of apps, then I stumbled over this app:AcePlayer
It lets you stream and download media via PSM. Especialy the download function is much more convinient for me then iTunes. So far everything works perfectly for me, so you might give it a try.
There is a Lite version of the app but since a few days the full version is free as well (however this might change sometime...). I tryd both versions and the adds in the "Lite" aren't to bothering.
I hope this is helpful for someone in any way.
And I want to thank everyone who works on and suports this extremly fine piece of software.
Sry for any spelling errors