I'm 5'2.5". My inseam is 27". I use six risers for all workouts with the high step. I did notice a difference. It is more intense, in L&G I get a little more winded doing all the step ups and in PLB the additional riser seems to really target the upper hamstring/lower glute more. My leg is not a 90 degree angle like is recommended, but I don't have knee problems (yet). I do think it is worth the purchase.
Susan C.M.