Really have no thoughts on them. Would be interesting to measure, but the weight movement would most likely not effect the MPF that much. Takes 10 grams to move the cg approximately .090″ (90/1000). Also interesting that it doesn’t say how much each of the weights weigh on their website, or at least I can’t find where it does, so I don’t know how much actual weight movement there is when you move them around. Moving weight around on irons has much less an effect than it does on drivers. A driver weighs 195-200 grams and is 460cc in size, so when you move 10 or 20 grams of weight, the percentage is higher of the total weight and you are usually moving it a longer distance, it can influence cg movement to a small degree. A typical #5 iron weights 254 grams and is much smaller in size, so your moving weight a smaller distance, and it takes a lot more weight to get to the percentage you need to effectively move the cg enough to make any significant playability difference. That’s what I know about cg, but again, I don’t know how much the weights weigh so I don’t know how much you can actually move on the SMS irons. Would be interesting to measure.