Replying to Sandisk SD cards

Looking to buy some more SD cards and have figured that San disk seem to be faster and hold up longer than brands like Transcend.

I was wondering if anyone thinks the extreme pro are worth double the price over the extremes..

The part that gets my interest is that the extreme pro claim to be water proof..

If anyone has experience with the extreme cards or has a different brand to recommend, much would be appreciated!

thanks