I did this one yesterday and yes, it is a killer. It really does creep up on you. The intensity is definately there. I am sore from it today but just my upper body from all the arms in the hi/lo section.
I used the same weights that she used except I used eight pounds instead of five for the standing leg extensions with a hammer curl.
It is hard for me to do the planks with straight arms because it makes my wrists sore, so when she does the straight arm planks, I do them with either a bent arm or flip over and do my own abs.
I think Step Fit is pretty intense too, but I dont see many comments about it here.
Love,
Madonna