I bought this on a lark because it was on Open Box auction for $8. When I got it I was underwhelmed but not badly disappointed because, well, $8 is not the end of the world. However, this effect was a reminder that you can’t judge magic or mentalism until you present it. What I thought to be a somewhat lame magic product actually has turned out to be a nice little addition to toss in between more involved routines. I base this evaluation purely on reactions, including from folks who are more than happy to tell me if they think something is good or if something sucks. I’ve received only very positive feedback from CUBE SUM. I will say that this effect is (in my opinion) not marketed correctly and those who purchase it will want to take the method but significantly modify presentation so as to individualize it stylistically. This is positioned, in the instructions, as primarily a “miracle calculation” effect. That is essentially true, but if you treat it only as such the impact is minimized. You can, for example, twist and turn it to work as a nice premonition and/or human lie-detector effect. Additionally, there is much discussion in the instructions about how to ditch “something” when in fact if you stage this in the correct context the participant can actually make the decision as to what needs to be ditched and it becomes part of the seeming “fairness” of the routine (that will be clear if you buy this). I also saw some criticism of this product based on the fact that these dice are color coded on all six sides. A few folks thought that this was a tip as to method when, in reality, good patter combining the elements of colors and numbers is a very effective technique for establishing the appearance that there are a couple zillion possible outcomes based on what happens. A pleasant surprise and reasonably priced even at full ticket cost. Walk-around mentalists and those with numerology type effects in their act might like it. Only warning: when you have your participant add up numbers --- HAVE THEM DOUBLE CHECK THEIR ADDITION!