I am trying to save some $ and punching/piercing my own dual cartos for my tank. I use a saddle press and it does the trick but maybe 50% of the time I get the dreaded e1 error and it wont work. Yet, I can use the same punched carto on my kgo and it works like a champ. Is the provari too sensitive to changes maybe? Anyone else seeing this happen-any suggestions other than paying the higher price to have them punched at the factory? Now that I have some tanks and really like them I hope the problem can be fixed. Too spoiled from the tank to go back to the old way.