I didn't like Factor Captor because it was easy to get a prime number in which you could easily win against someone, so it seemed kind of cheating, even though it was it was allowed. That made me feel guilty when I used the highest prime number on the board. However, I liked the strategy behind it and it helped me learn a lot.
Using an array helps you find factors because any time you find an array that doesn't have 1, 2, or more left out you can just count the dots on the top and left and you have your two factors. Then you can use another array to find more. Also, it lays out factors in such a open way that you can't do anything but immediately start learning them by heart.
I liked the lesson 1*6, page 16 because I learned a lot of prime numbers, as well as the relationship between composite and prime. I think prime numbers are very cool. I also like lesson 1*5 page 14 because Divisibility Rules are just plain helpful.