I think that designers of cartridges and cars should stick with good designs and allow them to remain affordable rather than trying to improve on something that needs no improvement. the result of "new and improved" may not be better and the raising of the price makes users of the original model feel angry at the company for pricing them out. I like the original 901 and feel it needs no improvement and now cannot afford a Mark 2 901. The company has alienated me in this regard.