French Fried Sweet Potatoes

Some of the health experts pointed out that you want to order sweet potatoes French fries rather than the regular potatoes, especially if you have diabetic problem.  In my case, I was curious which "sweet potatoes" is the best for the French fries.  I picked sweet potatoes (not YAMs). 
Lesson learned - watch closely the oil temperature during frying.  Due to sugar content of the sweet potatoes, they burn easily.  My sweet potato french fries did not turn out like the ones I ate at the Elephant bar, for example.  How do they do that light crusty look on it.... well, I will have to try it again, the next time.