Thanks for all the responses.
Sounds like no clear consensus, and no place around here to get full-fledged simulator time. I'm surprised a simulator would be more expensive to operate than a real helicopter, what with the maintenance costs, liability, and all that. I just watched an R-22 autorotation training video pointing out that more accidents happen from practice autorotations than from actual engine failures.
I decided to order X-Plane, a joystick to use as a cyclic, a throttle controller (to use as a collective), and pedals. I'm not sure this will accelerate my actual flight lessons much but it looks like fun. With the Seattle* maps maybe I'll learn my way around the local airfields.
I tried to fly the R-22 built into the demo version of X-Plane and couldn't get far with the keyboard. There are various third-party modules to emulate other helicopters.
* Speaking of Seattle, I was on the observation deck of the Columbia Tower this weekend and disappointed not to see helipads on top of the other office buildings.
--mj