Sorry, totally missed this - I haven’t been as active on the forum due to ongoing health problems.
Nik believes the setup and tuning stability is more reliable with the two post. Reading between the lines, 6posts are easier for a customer to mess up when changing setup or string gauge different from factory setup
I was simply told this is one the the lessons he’s learned over time from experience. Personally, I haven’t had any issues with the PRS 6 post trem but I tend to use a luthier for any major setup adjustments.