Wandering Adventure Party

My advice: only cook the toughest of meats for much longer than that. You can safely go longer, but the tenderness gets to be too much and you cross a line into unpleasantly soft.

Yours looks perfect though! What’d you season with?

It’s less for bigger pieces and more for tougher pieces. Shoulder, chuck and bottom round roast is what I usually use for long roast beef preparations. Given enough time the connective tissue breaks down into gelatin and it becomes wonderfully tender rather than mushy.
I like to cook it to rare and then sear or oven it to midum rare ish, which I like for sandwiches.

I like to grind some black pepper, salt, minced dried garlic and onion, and some mustard seeds on mine before cooking. Leaves a good flavor on the outside and you can take the juice in the bag with the spice that fell off and cook it down with some butter to make a really good savory spread.