On a really clear night, was able to expose to about 8 minutes.  Andromeda Galaxy was low but shots came out okay.  This was an unguided shot so guiding should help.  A skyglow filter would also help.

Did some PEC training and Smart Mount training (want to do some more polar alignment) but this has definitely improved the alignment.  Took a test shot (here) — removed the UV filter, stopped down the aperture and used larger files (but not RAW just yet) and the results are reasonable.