There is the R and X model, which uses longer shocks than the stock yfz. Then there is the new yfz (carbed model) that uses non piggyback shocks (junk).
I am not 100%, but i think yfz shocks are longer than stock LT250 shocks. I know the R/X shocks are longer. Issue with running longer shocks is this can cause extra stress on the ball joints and make them premature fail.