You don't say how fast the Panasonic is, my assumption is that its 12-18x or so. If its less than that, then your camera can probably write faster than that card can take data. So then the Ultra II would probably make a noticable difference.
The ultra IIs are about the fastest cards out there. but the reality is that most cameras can't write fast enough to take advantage of them.
So while the SanDisk should be faster than the Panasonic, it might not actually be worth paying the extra for the SanDisk when the performance differencecould be fairly small.