I just use a bipod myself but if going for a bench set up then the adjustable rests are easier to get set up than a single bag for an accurate shot. They have a soft pad between the rest and the rifle so it's not hard on hard. You can use just a bag out front and it will work fine but you will need to find one that is the proper height or you will be having to find ways to make it shorter or taller out front.
I have the Run and Gun for barricades and alternative position shooting. If I'm on the bench, I have the Red Tac Rear Bag for the butt stock. Little pricey when you compare, but worth the coin I dropped on them.