Sparky,
The reason I use the 185 internal on the pastramied beef brisket is that is a pretty good compromise between the remaining moisture left in the meat and the tenderness of the final product. A lesser temperature will almost always give you a more moist product but one that is more difficult the bite and chew even if it is sliced real thin. I have tried as low as 165 internal but is was just too tough. Any temp over about 185 and the ends of the meat may start falling apart.
N. Ontario Smoker,
Sir, I can't answer your question using the #1 cure in place of the Tenderquick. I just don't know.
Dave