If you are looking at buying SD or CF cards, realize that all the main brands and even some second tier (like KINGMAX) work equally well. They all use the same technology and they all have about the same chance for problems. The thing is, 95% of buyers of ANY of these brands will have NO problems and they will work flawlessly for years.
The other 5% will either have a problem right out of the box or within a few months. This is true of ALL brands. For every basher of Kingston, there is a basher of Sandisk, etc etc. Flash memory is prone to have the odd bad unit here and there, so don't give up on a nicely priced brand (or one with a rebate) just becuase you fell in that 5% once.
The best way to protect yourself is to FILL THE CARD with data (pictures, etc) ALL THE WAY TO THE MAX and then try to retrieve that data back in your computer. This will at least run the card through it's paces once and will reduce the chance of finding a bad sector much later in the life of the card. (Yes, one bad sector, way up in the higher memory area, is enough to ruin ALL the photo's on the card). You stil may have problem in a few months if you are part of the 5%, but you will reduce those chances considerably.
So price shop and get the best deal you can. Also worth noting is that oftentimes Kingston allows TWO (2) rebates per household as opposed to the standard one rebate per household (and you should mail the two in the SAME envelope). But don't just take my word for it, read the rebate (if there is one) to make sure of the limit per household.
Anyway, just get your best price and run the card through it's paces when you get it and you should be happy 95% of the time or better.