<<If I recall, Chris Z. carried about 90 pounds in the back of his 360, didn't like it very well and mentioned he wouldn't do it again.>>
Gary,
-first half is correct.  When my wife and I go on long camping trips we end up with 80-90 lbs of gear in the back.  The reduced stability is noticeable when cruising up high (15-18k)in this loading condition.  The combination of aft CG and very thin air make trimming more difficult-especially roll.  Down low it doesn't stand out as much unless you consciously look for it.  If you give the stick a step input and observe the hands-free response, you can see the difference.  The only noticeable difference down low is the reduced stick force in the flare.  I have flown in this condition many times over the years.  80-90 lbs is my baggage limit (given no change in passenger weight) based on the stability response in high altitude cruise.  
-battery behind seat
-large tail
-long engine mount

Chris Zavatson
N91CZ
360std