Well, good point in wanting to know the compatibility first:-) I tried to load my EXR-3 with GW-7 styles, and although they are pretty similar, one style passed right, and the other has frozen my synth and corrupted the usb procedure, so I had to return to factory presets - and then download all the styles from Roland page (thank god, they were there!) because they were then erased.

As for special styles, seems no one knows how to get them free of charge:-) And I still haven't found any commercial ones, too:-((