Fractional piston ownership - what say you?

I am a long time subscriber to Flying Mag. I have read Robert Goyer's
articles on shared/fractional piston ownership, and decided to take a
look at the numbers.

His most recent article in the Dec2006 Flying states:

SR22-G2 (1/8th share) = $71,900 (Note that $71,900 * 8 = $575k)
$760 monthly management fee
$90 hourly operating cost.

This 'buys' the owner access to 75 hours per year of flying time, with
21 overnights.

Adding up the annual costs for these 75 hrs.
$4,314 (6 percent simple interest on $71,900)
$9,120 ($760/month * 12 months)
$6,750 (hourly cost * 75hrs)
--------------
$20,184 or $269 per flight hour

One piece that is missing is the depreciation of the aircraft. One
can expect the SR22 to be worth a lot less in a few years with the 8
users putting an approximate 500hrs/year on the plane.

So is this a good deal?

To me, it seems like a quite large amount to spend per hour for a
single, even if it is a 'technologically advanced aircraft'.

One of the Chicago area flying clubs is asking $218/hr, and they have
two SR22s online, as well as ~20 other planes.

-Nathan