I can't tell you if they are similiar to the HRS platforms or not. I have seen the HRS platforms and in person they do not look that much alike. How they perform compared to HRS I do not know - they do cost a lot less than HRS platforms however and the performance improvement that I heard was good enough for me given the price point.
Buconero117 - I have tried Bright Star audio sand boxes in the past, which I am sure are as good as a DIY sandbox, and I did not hear much, if any of a performance improvement. The Appogg Systems platforms do make a very audible performance improvement in my system to my ears. I did not do any comparison of them to anything else and don't plan to. Given their price point, the real performance improvement is a worthwhile upgrade for me.