I paid three times. Bought the 440 source balanced kit, new machine guy said he should check/balance the crank, put it together and had vibration, took apart and had trusted shop take out the weight the other shop put in to get it back to where it was originally....

After that, on my next stroker, I bought a nice scale and rod holding fixture and checked all the weights myself and they were very close, within a gram, so I used the kit as delivered and no problems with vibration, it is nice and smooth.