Honestly, no one can answer this but your snake. Some will switch no problem, others will NEVER take f/t.
How old are they and how many grams are they? What size are you feeding them? Switching to f/t won't change their growth rate, only larger and/or more frequent meals will do this. Both of which you can do with live, p/k or f/t. Most breeders/keeps will recommend feeding your snake 10-15% of its body weight every 5-7 days for growing/younger/breeding balls.