Good crockpot/slow cooker roast recipe?

Add onions

Bed of onion rings on the bottom, 2 cups of water, 2 bullion cubes, 4 cloves garlic, salt and pepper on the roast, and then a cup of buttermilk over the top. It'll be good. Did it yesterday with a game roast.

Brown the roast on the stove first, then into the crock.

Onion soup mix and 2 cans of cream of mushroom.

Do people use a slow cooker over a Dutch oven for convenience and easier temperature control?

I think searing a roast in a Dutch oven,.them trenching the roast, sweat onions, garlic, etc over medium low heat, season, add roast back in, then add stock or whatever, and put it in the oven low and slow.

Ive never done either, but I would think the Dutch oven would be much more flavorful.