Do you sear on grill or pan?
yes. We've seared it right afterwards very briefly on each side. More for the purpose of making it it hotter than adding more flavor/texture.
131 degrees is sort of warm, so the sear heated it up. Also, we've placed the whole Sous Vide unit on a wall timer and had it turn off at 12:30pm on Shabbos, removed it, sliced it, and served it straight! It was delicious! (It was 2 halves of a shoulder roast cooking in two bags from Friday afternoon.) 24 hours at 132 degrees for shoulder roast. 48 hours at 131 degrees for chuck steak.