I read the first and second Mistborn books. I liked the first one - I thought Kelsier was a compelling lead character. I really had to struggle through the second to the point where I didn't want to read the third.
I don't think Sanderson is a great writer. I think he's fallen into the trap that a lot of fantasy writers do where they think that complex magic systems and enough worldbuilding to fill a history textbook are a good substitute for character or story. Vin was as boring a main character you can get and her supposedly undying love for that one guy was completely and utterly sexless, as in, I had no indication that these characters were into each other aside from them saying it. Their romance scenes felt wooden and unbelievable. None of the other characters were any more fleshed out than one or two word descriptions, and all were immediately forgettable. About the only character whose name I can remember besides Kelsier (because I thought he was the best character in the lot) and Vin (because she was the main character) was Ham and that's only because I laughed everytime I saw it.