ChrisLehrer,
I have a set of the KitchenAid attachments and I love them. Before I donated my Atlas to Goodwill, I never really used it because it was such a PITA. Now I make fresh linguini every time I make Bolognese, which is about once a month.
OregonYeti, I used exactly the same recipe and preparation method when I switched from the Atlas to the KitchenAid. Maybe my Atlas was just defective, but it still took three hands to operate. By comparison, the process with my KA is just a simple joy.
As for the electric drive on the Atlas... I took a look at one of those once. If I already had an Atlas, maybe I'd think it was worth it... But the motor is about the same price, by itself, as the roller, spaghetti and linguini cutters for the KA. Add in the price of the Atlas machine itself, and it's more expensive to go that route, plus you've got the extra storage space to spend.