For my money, it would be Instant Article Wizard. With AB, you get good articles that are 75% unique but they are tip based and also only on certain subjects. You could amalgamate several articles but they may not be in the area you need. With IAW you can write articles on almost any subject, provided there are articles already on the net. You get a limited version of TBS with IAW. TBS is for spinning articles you have written. IAF is for producing articles quickly using templates.