Choose Your Own Adventure books were very similar to Fighting Fantasy however there are two major differences - Fighting Fantasy was written for the pre-teens up to young adults as the themes were too dark for younger kids, and you had to use dice in order to battle creatures, test your luck, and increase / decrease stamina.

For instance - if you have a skill and stamina rating of 9 and 18 respectively, when fighting you would roll two dice and add the total to your skill. You would then do the same for the creature you are fighting and whoever had the highest 'skill' total would inflict damage - minus 2 stamina points. You would then continue this until either you or the creature had zero stamina i.e. dead.

Being a Transformers fan and a Fighting Fantasy fan I used to make up skill and stamina ratings for my Transformer toys (more often than not just using the Tech Specs ratings) and had them fight using the above method.

I've never owned any of the Transformer game books but have read about them. Been tempted more than once to buy some from Ebay.