abby02 wrote:

the disadvantage of junior alchemy is that it takes the class of the higher rank material even if it is not the main material... for example if u compound titanium alloy with wolf tooth, the class of the compounded item will be canine not a titanium

I've actually found that when a compound fails with junior alchemy, it commonly returns the higher ranked material used, even if it isn't the main material. So really, it's an advantage because you will (generally speaking) lose less of you higher ranked items.