The only advantage I see that the 9 inch has is the fact that gear changes are A LOT easier and you have more gear ratios to choose from with the 9 inch.
I have never heard of anyone blowing out an 8.8 rear on a car that is run on the street.
If you have more than 500 RWH then I would say it couldn't be very streetable.
------------------
'82 GT 351W,BBK shorties,
Comp Cam,edelbrock intake
625 cfm carter carb. c-4 tranny w/ pro stick shifter. 4 core radiator
Mallory distributor. 3:27
.........................
|