[JoeSchmuck]

Ok that's odd.. If it just been sitting in the pi. Mine was/is also brand new 16GB Kingston class 10 but clearly bad buildt, once I taped it together again it works great so it was just the case the innards are super.

The soldering will probably work fine depending on how well your soldering skills are, you should be able to get even solder on each point, maybe its enough to give it some solder and then suck it back up using either a tin sucker or better some fine copper mesh. If you put that between the contact point and the solder iron tip the copper mesh will draw all excess solder of the contact point and you will have a nice thin even layer, the question is if that is enough. :/

Also those big contact points will draw heat fast to the inner parts, and the plastic separating the points so be quick as you can. I don't expect you can take it apart while doing it to have more control?

You can always experiment on a old pice of electronics with about the same exposed copper as the sd card and see how it behaves.

Good luck mate.. Like to hear how it goes.

This clearly isn't the thread to discuss this defect however there should be a root cause analysis done to determine the real cause of the failures. Maybe it's because there is no support for the back of the SD Card and the contact fingers are stronger than we think or maybe just not flexible enough to give a little thus creating too much force on the SD package and causing it to break. I myself will take a look into it and see if there is a better SD card socket that I could replace it with or possibly some sort of modification that would work. Again, maybe a different thread in the RPI forum would be better? Also I wouldn't place solder on top of the gold contacts of an SD card but that is just my opinion.