I have a set of Jesse's for my Tiger and like them. They are rugged and weatherproof and a good size, being over 100L combined for the two panniers in my case. I had one near side get off on pavement and the case took the punch with no distortion of the case or mounting framework, only ground down the aluminum on the corner. They are not the lowest priced though, so could be a little overkill for just picking up groceries. A 4L jug of milk does fit nicely into them.
Here's a link: