Hi asA have you run a cheyenne pen as well to compare the two machines would be very interested to hear, also what is the grip made of that holds the cartridges will it hold up to consent changing of cartridges also what is the length of stroke does the machine stats say you can achieve,Be interested to hear a small review on the ez pen say quite a few more could be interested to hear your take on the over all machine build quality, materials used to build and if it only suits EZ certs cheers for posting asA looking forward to hearing a little review.