Sorry to disappoint but sweet potatoes can be just as toxic. All varieties of potatoes have the same potential toxicity due to glycoalkaloids. But as said above, it's really quite rare. Don't eat them if they've started sprouting, cut off any green areas and make sure and store them properly(not too long) and you'll be perfectly fine.

I do vote for sweet potatoes over most other types, they're healthier and tastier too!