Does having faster SD-cards matter?

Ey guys,

I have this JVC Everio GZ-MS90 camera and a Sansa Fuze+ MP3 player with SD-card port. I currently use rank 4 SD-cards for both. Would I notice any speed or quality difference if I would use a card like the Sandisk Extreme Pro (rank 10)? I could imagine that the camera would become more responsive and the MP3 player showing slightly reduced loading times… Does it really have a noticable effect?

Thanks in advance.