Replying to Full tilt flex question

alright so i am purchasing some fulltilt booters (blue and yellow ones from a year or two ago) from a friend of mine. They come with a flex 2 tongue, which is pretty damn soft. i was wondering if im used to a medium-stiff boot would i be okay to ski with the flex 2 tongues for preseason? I just dont know how much a difference it will make or if i will risk an injury or something. basically just until christmass when i can get some stiffer tongues.