[APML] Prime Focus AP: what can I expect?

[MMalone116@aol.com]

I welcome any opinions on the limitations (specifically exposure times) I should expect doing PF AP with my LX-90 SCT.

My planned setup would include:
LX-90 off-axis autoguided with Pictor 201XT
use f/6.3 focal reducer for deep sky
assume fairly good polar aligning (hoping to not have to drift align everytime)
assume fairly good collimation
assume fresh batteries
limited dark site (all little dipper stars are visible most of the time, but just barely)
Nikon F3 camera with 'D' screen and 8x Loupe
Will the use of vibration isolation pads make a difference?
Should I counterbalance the weight of the camera?

-Mike M.