Both my friend and i use this. My friend has a very good-doer and he gets fed 2 cups per day with a bit of chaff. I use it with allen and pages ride and relax as he events so he gets both for a wee bit extra energy. I think its great and also dont have to feed extra suppliments etc!
I've tried it for both of mine & for some reason it sent tem both loopy, in fact downright dangerous would be a better description in one case though in fairess he can be a tricky one to feed. I now use Top Spec Lite (same price as Lo Cal & meant to be even lower calorie) & have no problems.
I've just started my veteran good doer on it as he came out of the winter looking a bit duller than normal. He's doing fine, eats every scrap, looking great again, laid back as ever, in short, I love it.